Deprecate GetModelIsPrivate and its usages

- remove App:before so we can use #app-navigation to access the mobile header
- fix mobile postStream scroll top margin adjustment

.gitattributes

@@ -11,3 +11,5 @@ phpunit.xml export-ignore
 tests export-ignore
 
 js/dist/* -diff
+
+* text=auto eol=lf

CHANGELOG.md

@@ -1,5 +1,102 @@
 # Changelog
 
+## [0.1.0-beta.14](https://github.com/flarum/core/compare/v0.1.0-beta.13...v0.1.0-beta.14)
+
+### Added
+
+- Check dependencies before enabling / disabling extensions (https://github.com/flarum/core/pull/2188)
+- Set up temporary infrastructure for TypeScript in core (https://github.com/flarum/core/pull/2206)
+- Better UI for request error modals (https://github.com/flarum/core/pull/1929)
+- Display name extender, tests, frontend UI (https://github.com/flarum/core/pull/2174)
+- Scroll to post or show alert when editing a post from another page (https://github.com/flarum/core/pull/2108)
+- Feature to test email config by sending an email to the current user (https://github.com/flarum/core/pull/2023)
+- Allow searching users by group ID using the group gambit (https://github.com/flarum/core/pull/2192)
+- Use `liveHumanTimes` helper to update times without reload/rerender (https://github.com/flarum/core/pull/2208)
+- View extender, tests (https://github.com/flarum/core/pull/2134)
+- User extender to replace `PrepareUserGroups` (https://github.com/flarum/core/pull/2110)
+- Increase extensibility of skeleton PHP (https://github.com/flarum/core/pull/2308, https://github.com/flarum/core/pull/2318)
+- Pass a translator instance to `getEmailSubject` in `MailableInterface` (https://github.com/flarum/core/pull/2244)
+- Force LF line endings on windows (https://github.com/flarum/core/pull/2321)
+- Add a `Link` component for internal and external links (https://github.com/flarum/core/pull/2315)
+- `ConfirmDocumentUnload` component
+- Error handler middleware can now be manipulated by the middleware extender
+
+### Changed
+
+- Update to Mithril 2 (https://github.com/flarum/core/pull/2255)
+- Stop storing component instances (https://github.com/flarum/core/issues/1821, https://github.com/flarum/core/issues/2144)
+- Update to Laravel 6.x (https://github.com/flarum/core/issues/2055)
+- `Flarum\Foundation\Application` no longer implements `Illuminate\Contracts\Foundation\Application` (#2142)
+- `Flarum\Foundation\Application` no longer inherits `Illuminate\Container\Container` (#2142)
+- `paths` have been split off from `Flarum\Foundation\Application` into `Flarum\Foundation\Paths`, which can be injected where needed  (#2142)
+- `Flarum\User\Gate` no longer implements `Illuminate\Contracts\Auth\Access\Gate` (https://github.com/flarum/core/pull/2181)
+- Improve Group Gambit performance (https://github.com/flarum/core/pull/2192)
+- Switch to `dayjs` from `momentjs` (https://github.com/flarum/core/pull/2219)
+- Don't create a `bio` column in `users` for new installations (https://github.com/flarum/core/pull/2215)
+- Start converting core JS to TypeScript (https://github.com/flarum/core/pull/2207)
+- Make Carbon an explicit dependency (https://github.com/flarum/core/commit/3b39c212e0fef7522e7d541a9214ff3817138d5d)
+- Use Symfony's translator interface instead of Laravel's (https://github.com/flarum/core/pull/2243)
+- Use newer versions of fontawesome (https://github.com/flarum/core/pull/2274)
+- Use URL generator instead of `app()->url()` where possible (https://github.com/flarum/core/pull/2302)
+- Move config from `config.php` into an injectable helper class (https://github.com/flarum/core/pull/2271)
+- Use reserved TLD for bogus and test urls (https://github.com/flarum/core/commit/6860b24b70bd04544dde90e537ce021a5fc5a689)
+- Replace `m.stream` with `flarum/utils/Stream` (https://github.com/flarum/core/pull/2316)
+- Replace `affixedSidebar` util with `AffixedSidebar` component
+- Replace `m.withAttr` with `flarum/utils/withAttr`
+- Scroll Listener is now passive, performance improvement (https://github.com/flarum/core/pull/2387)
+
+### Fixed
+
+- `generate:migration` command for extensions (https://github.com/flarum/core/commit/443949f7b9d7558dbc1e0994cb898cbac59bec87)
+- Container config for `UninstalledSite` (https://github.com/flarum/core/commit/ecdce44d555dd36a365fd472b2916e677ef173cf)
+- Tooltip glitch on page chang (https://github.com/flarum/core/issues/2118)
+- Using multiple extenders in tests (https://github.com/flarum/core/commit/c4f4f218bf4b175a30880b807f9ccb1a37a25330)
+- Header glitch when opening modals (https://github.com/flarum/core/pull/2131)
+- Ensure `SameSite` is explicitly set for cookies (https://github.com/flarum/core/pull/2159)
+- Ensure `Flarum\User\Event\AvatarChanged` event is properly dispatched (https://github.com/flarum/core/pull/2197)
+- Show correct error message on wrong password when changing email (https://github.com/flarum/core/pull/2171)
+- Discussion unreadCount could be higher than commentCount if posts deleted (https://github.com/flarum/core/pull/2195)
+- Don't show page title on the default route (https://github.com/flarum/core/pull/2047)
+- Add page title to `All Discussions` page when it isn't the default route (https://github.com/flarum/core/pull/2047)
+- Accept `'0'` as `false` for `flarum/components/Checkbox` (https://github.com/flarum/core/pull/2210)
+- Fix PostStreamScrubber background (https://github.com/flarum/core/pull/2222)
+- Test port on BaseUrl tests (https://github.com/flarum/core/pull/2226)
+- `UrlGenerator` can now generate urls with optional parameters (https://github.com/flarum/core/pull/2246)
+- Allow `less` to be compiled independently of Flarum (https://github.com/flarum/core/pull/2252)
+- Use correct number abbreviation (https://github.com/flarum/core/pull/2261)
+- Ensure avatar html uses alt tags for accessibility (https://github.com/flarum/core/pull/2269)
+- Escape regex when searching (https://github.com/flarum/core/pull/2273)
+- Remove unneeded semicolons inserted during JS compilation (https://github.com/flarum/core/pull/2280)
+- Don't require a username/password for SMTP (https://github.com/flarum/core/pull/2287)
+- Allow uppercase entries for SMTP encryption validation (https://github.com/flarum/core/pull/2289)
+- Ensure that the right number of posts is returned from list posts API (https://github.com/flarum/core/pull/2291)
+- Fix a variety of PostStream bugs (https://github.com/flarum/core/pull/2160, https://github.com/flarum/core/pull/2160)
+- Sliding discussion glitch on mobile (https://github.com/flarum/core/pull/2324)
+- Sliding discussion button in wrong place (https://github.com/flarum/core/pull/2330, https://github.com/flarum/core/pull/2383)
+- Sliding discussion glitch on mobile (https://github.com/flarum/core/pull/2381)
+- Fix PostStream for posts with top margins, and scrubber position when scrolling below posts (https://github.com/flarum/core/pull/2369)
+
+### Removed
+
+- `Flarum\Event\AbstractConfigureRoutes` event class
+- `Flarum\Event\ConfigureApiRoutes` event class
+- `Flarum\Event\ConfigureForumRoutes` event class
+- `Flarum\Console\Event\Configuring` event class
+- `Flarum\Event\ConfigureModelDates` event class
+- `Flarum\Event\ConfigureLocales` event class
+- `Flarum\Event\ConfigureModelDefaultAttributes` event class
+- `Flarum\Event\GetModelRelationship` event class
+- `Flarum\User\Event\BioChanged` event class
+- `Flarum\Database\MigrationServiceProvider` moved into `Flarum\Database\DatabaseServiceProvider`
+- Unused `admin/components/Widget` component (`admin/component/DashboardWidget` should be used instead)
+- Mandrill mail driver (https://github.com/flarum/core/commit/bca833d3f1c34d45d95bf905902368a2753b8908)
+
+### Deprecated
+
+- `Flarum\User\Event\GetDisplayName` event class
+- Global path helpers, `Flarum\Foundation\Application` path methods (https://github.com/flarum/core/pull/2155)
+- `Flarum\User\AssertPermissionTrait` (https://github.com/flarum/core/pull/2044)
+
 ## [0.1.0-beta.13](https://github.com/flarum/core/compare/v0.1.0-beta.12...v0.1.0-beta.13)
 
 ### Added

README.md

@@ -1,12 +1,14 @@
-<p align="center"><img src="https://flarum.org/img/logo.png"></p>
+<p align="center"><img src="https://flarum.org/assets/img/logo.png"></p>
 
 <p align="center">
-<a href="https://travis-ci.org/flarum/core"><img src="https://travis-ci.org/flarum/core.svg" alt="Build Status"></a>
-<a href="https://packagist.org/packages/flarum/core"><img src="https://poser.pugx.org/flarum/core/d/total.svg" alt="Total Downloads"></a>
-<a href="https://packagist.org/packages/flarum/core"><img src="https://poser.pugx.org/flarum/core/v/stable.svg" alt="Latest Stable Version"></a>
-<a href="https://packagist.org/packages/flarum/core"><img src="https://poser.pugx.org/flarum/core/license.svg" alt="License"></a>
+<a href="https://github.com/flarum/core/actions?query=workflow%3ATests"><img src="https://github.com/flarum/core/workflows/Tests/badge.svg" alt="PHP Tests"></a>
+<a href="https://packagist.org/packages/flarum/core"><img src="https://img.shields.io/packagist/dt/flarum/core" alt="Total Downloads"></a>
+<a href="https://packagist.org/packages/flarum/core"><img src="https://img.shields.io/github/v/release/flarum/core?sort=semver" alt="Latest Version"></a>
+<a href="https://packagist.org/packages/flarum/core"><img src="https://img.shields.io/packagist/l/flarum/core" alt="License"></a>
+<a href="https://github.styleci.io/repos/28257573"><img src="https://github.styleci.io/repos/28257573/shield?style=flat" alt="StyleCI"></a>
 </p>
 
+
 ## About Flarum
 
 **[Flarum](https://flarum.org/) is a delightfully simple discussion platform for your website.** It's fast and easy to use, with all the features you need to run a successful community. It is designed to be:
@@ -32,4 +34,3 @@ If you discover a security vulnerability within Flarum, please send an e-mail to
 ## License
 
 Flarum is open-source software licensed under the [MIT License](https://github.com/flarum/flarum/blob/master/LICENSE).
-

composer.json

@@ -10,7 +10,7 @@
             "email": "franz@develophp.org"
         },
         {
-            "name": "Daniel Klabbers",
+            "name": "Daniël Klabbers",
             "email": "daniel@klabbers.email",
             "homepage": "https://luceos.com"
         },
@@ -27,6 +27,10 @@
         {
             "name": "Matthew Kilgore",
             "email": "matthew@kilgore.dev"
+        },
+        {
+          "name": "Alexander (Sasha) Skvortsov",
+          "email": "askvortsov@flarum.org"
         }
     ],
     "support": {
@@ -37,7 +41,7 @@
     "require": {
         "php": ">=7.2",
         "axy/sourcemap": "^0.1.4",
-        "components/font-awesome": "5.9.*",
+        "components/font-awesome": "^5.14.0",
         "dflydev/fig-cookies": "^2.0.1",
         "doctrine/dbal": "^2.7",
         "franzl/whoops-middleware": "^0.4.0",
@@ -72,11 +76,11 @@
         "psr/http-server-handler": "^1.0",
         "psr/http-server-middleware": "^1.0",
         "s9e/text-formatter": "^2.3.6",
-        "symfony/config": "^3.3",
-        "symfony/console": "^4.2",
-        "symfony/event-dispatcher": "^4.3.2",
-        "symfony/translation": "^3.3",
-        "symfony/yaml": "^3.3",
+        "symfony/config": "^4.3.4",
+        "symfony/console": "^4.3.4",
+        "symfony/event-dispatcher": "^4.3.4",
+        "symfony/translation": "^4.3.4",
+        "symfony/yaml": "^4.3.4",
         "tobscure/json-api": "^0.3.0",
         "wikimedia/less.php": "^3.0"
     },

js/package-lock.json

@@ -1075,6 +1075,11 @@
       "integrity": "sha512-rr+OQyAjxze7GgWrSaJwydHStIhHq2lvY3BOC2Mj7KnzI7XK0Uw1TOOdI9lDoajEbSWLiYgoo4f1R51erQfhPQ==",
       "dev": true
     },
+    "@types/mithril": {
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/@types/mithril/-/mithril-2.0.3.tgz",
+      "integrity": "sha512-cZHOdO2IiXYeyjeDYdbOisSdfaJRzfmRo3zVzgu33IWTMA0KEQObp9fdvqcuYdPz93iJ1yCl19GcEjo/9yv+yA=="
+    },
     "@types/parse-json": {
       "version": "4.0.0",
       "resolved": "https://registry.npmjs.org/@types/parse-json/-/parse-json-4.0.0.tgz",
@@ -3551,9 +3556,9 @@
       "integrity": "sha1-TkMekrEalzFjaqH5yNHMvP2reN8="
     },
     "jquery": {
-      "version": "3.4.1",
-      "resolved": "https://registry.npmjs.org/jquery/-/jquery-3.4.1.tgz",
-      "integrity": "sha512-36+AdBzCL+y6qjw5Tx7HgzeGCzC81MDDgaUP8ld2zhx58HdqXGoBd+tHdrBMiyjGQs0Hxs/MLZTu/eHNJJuWPw=="
+      "version": "3.5.1",
+      "resolved": "https://registry.npmjs.org/jquery/-/jquery-3.5.1.tgz",
+      "integrity": "sha512-XwIBPqcMn57FxfT+Go5pzySnm4KWkT1Tv7gjrpT1srtf8Weynl6R273VJ5GjkRb51IzMp5nbaPjJXMWeju2MKg=="
     },
     "jquery.hotkeys": {
       "version": "0.1.0",
@@ -3807,9 +3812,9 @@
       }
     },
     "mithril": {
-      "version": "0.2.8",
-      "resolved": "https://registry.npmjs.org/mithril/-/mithril-0.2.8.tgz",
-      "integrity": "sha512-9XuGnVmS2OyFexUuP/CcJFFJjHLM+RGYBxyVRNyQ6khbMfDJIF/xyZ4zq18ZRfPagpFmWUFpjHd5ZqPULGZyNg=="
+      "version": "2.0.4",
+      "resolved": "https://registry.npmjs.org/mithril/-/mithril-2.0.4.tgz",
+      "integrity": "sha512-mgw+DMZlhMS4PpprF6dl7ZoeZq5GGcAuWnrg5e12MvaGauc4jzWsDZtVGRCktsiQczOEUr2K5teKbE5k44RlOg=="
     },
     "mixin-deep": {
       "version": "1.3.2",
@@ -4541,11 +4546,6 @@
       "integrity": "sha512-mUdIBBvdn0PLOeP3TEkMH7HHeUP3GjsXCwKarjv/kGmUFOYg1VqEemKhoQpWMu6X2I8kHeuVdGibLGkVK+/5Qw==",
       "dev": true
     },
-    "serialize-javascript": {
-      "version": "2.1.2",
-      "resolved": "https://registry.npmjs.org/serialize-javascript/-/serialize-javascript-2.1.2.tgz",
-      "integrity": "sha512-rs9OggEUF0V4jUSecXazOYsLfu7OGK2qIn3c7IPBiffz32XniEp/TX9Xmc9LQfK2nQ2QKHvZ2oygKUGU0lG4jQ=="
-    },
     "set-blocking": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/set-blocking/-/set-blocking-2.0.0.tgz",
@@ -4895,21 +4895,29 @@
       }
     },
     "terser-webpack-plugin": {
-      "version": "1.4.3",
-      "resolved": "https://registry.npmjs.org/terser-webpack-plugin/-/terser-webpack-plugin-1.4.3.tgz",
-      "integrity": "sha512-QMxecFz/gHQwteWwSo5nTc6UaICqN1bMedC5sMtUc7y3Ha3Q8y6ZO0iCR8pq4RJC8Hjf0FEPEHZqcMB/+DFCrA==",
+      "version": "1.4.5",
+      "resolved": "https://registry.npmjs.org/terser-webpack-plugin/-/terser-webpack-plugin-1.4.5.tgz",
+      "integrity": "sha512-04Rfe496lN8EYruwi6oPQkG0vo8C+HT49X687FZnpPF0qMAIHONI6HEXYPKDOE8e5HjXTyKfqRd/agHtH0kOtw==",
       "requires": {
         "cacache": "^12.0.2",
         "find-cache-dir": "^2.1.0",
         "is-wsl": "^1.1.0",
         "schema-utils": "^1.0.0",
-        "serialize-javascript": "^2.1.2",
+        "serialize-javascript": "^4.0.0",
         "source-map": "^0.6.1",
         "terser": "^4.1.2",
         "webpack-sources": "^1.4.0",
         "worker-farm": "^1.7.0"
       },
       "dependencies": {
+        "serialize-javascript": {
+          "version": "4.0.0",
+          "resolved": "https://registry.npmjs.org/serialize-javascript/-/serialize-javascript-4.0.0.tgz",
+          "integrity": "sha512-GaNA54380uFefWghODBWEGisLZFj00nS5ACs6yHa9nLqlLpVLO8ChDGeKRjZnV4Nh4n0Qi7nhYZD/9fCPzEqkw==",
+          "requires": {
+            "randombytes": "^2.1.0"
+          }
+        },
         "source-map": {
           "version": "0.6.1",
           "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.6.1.tgz",

js/package.json

@@ -3,17 +3,18 @@
   "name": "@flarum/core",
   "dependencies": {
     "@babel/preset-typescript": "^7.10.1",
+    "@types/mithril": "^2.0.3",
     "bootstrap": "^3.4.1",
     "classnames": "^2.2.5",
     "color-thief-browser": "^2.0.2",
     "dayjs": "^1.8.28",
     "expose-loader": "^0.7.5",
     "flarum-webpack-config": "0.1.0-beta.10",
-    "jquery": "^3.4.1",
+    "jquery": "^3.5.1",
     "jquery.hotkeys": "^0.1.0",
     "lodash-es": "^4.17.14",
     "m.attrs.bidi": "github:tobscure/m.attrs.bidi",
-    "mithril": "^0.2.8",
+    "mithril": "^2.0.4",
     "punycode": "^2.1.1",
     "spin.js": "^3.1.0",
     "webpack": "^4.43.0",

js/shims.d.ts

@@ -0,0 +1,32 @@
+// Mithril
+import Mithril from 'mithril';
+
+// Other third-party libs
+import * as _dayjs from 'dayjs';
+import * as _$ from 'jquery';
+
+// Globals from flarum/core
+import Application from './src/common/Application';
+
+/**
+ * flarum/core exposes several extensions globally:
+ *
+ * - jQuery for convenient DOM manipulation
+ * - Mithril for VDOM and components
+ * - dayjs for date/time operations
+ *
+ * Since these are already part of the global namespace, extensions won't need
+ * to (and should not) bundle these themselves.
+ */
+declare global {
+  const $: typeof _$;
+  const m: Mithril.Static;
+  const dayjs: typeof _dayjs;
+}
+
+/**
+ * All global variables owned by flarum/core.
+ */
+declare global {
+  const app: Application;
+}

js/src/admin/AdminApplication.js

@@ -27,15 +27,19 @@ export default class AdminApplication extends Application {
    * @inheritdoc
    */
   mount() {
-    m.mount(document.getElementById('app-navigation'), Navigation.component({ className: 'App-backControl', drawer: true }));
-    m.mount(document.getElementById('header-navigation'), Navigation.component());
-    m.mount(document.getElementById('header-primary'), HeaderPrimary.component());
-    m.mount(document.getElementById('header-secondary'), HeaderSecondary.component());
-    m.mount(document.getElementById('admin-navigation'), AdminNav.component());
+    // Mithril does not render the home route on https://example.com/admin, so
+    // we need to go to https://example.com/admin#/ explicitly.
+    if (!document.location.hash) document.location.hash = '#/';
 
-    m.route.mode = 'hash';
+    m.route.prefix = '#';
     super.mount();
 
+    m.mount(document.getElementById('app-navigation'), { view: () => Navigation.component({ className: 'App-backControl', drawer: true }) });
+    m.mount(document.getElementById('header-navigation'), Navigation);
+    m.mount(document.getElementById('header-primary'), HeaderPrimary);
+    m.mount(document.getElementById('header-secondary'), HeaderSecondary);
+    m.mount(document.getElementById('admin-navigation'), AdminNav);
+
     // If an extension has just been enabled, then we will run its settings
     // callback.
     const enabled = localStorage.getItem('enabledExtension');

js/src/admin/components/AdminLinkButton.js

@@ -10,11 +10,7 @@
 import LinkButton from '../../common/components/LinkButton';
 
 export default class AdminLinkButton extends LinkButton {
-  getButtonContent() {
-    const content = super.getButtonContent();
-
-    content.push(<div className="AdminLinkButton-description">{this.props.description}</div>);
-
-    return content;
+  getButtonContent(children) {
+    return [...super.getButtonContent(children), <div className="AdminLinkButton-description">{this.attrs.description}</div>];
   }
 }

js/src/admin/components/AdminNav.js

@@ -31,62 +31,74 @@ export default class AdminNav extends Component {
 
     items.add(
       'dashboard',
-      AdminLinkButton.component({
-        href: app.route('dashboard'),
-        icon: 'far fa-chart-bar',
-        children: app.translator.trans('core.admin.nav.dashboard_button'),
-        description: app.translator.trans('core.admin.nav.dashboard_text'),
-      })
+      AdminLinkButton.component(
+        {
+          href: app.route('dashboard'),
+          icon: 'far fa-chart-bar',
+          description: app.translator.trans('core.admin.nav.dashboard_text'),
+        },
+        app.translator.trans('core.admin.nav.dashboard_button')
+      )
     );
 
     items.add(
       'basics',
-      AdminLinkButton.component({
-        href: app.route('basics'),
-        icon: 'fas fa-pencil-alt',
-        children: app.translator.trans('core.admin.nav.basics_button'),
-        description: app.translator.trans('core.admin.nav.basics_text'),
-      })
+      AdminLinkButton.component(
+        {
+          href: app.route('basics'),
+          icon: 'fas fa-pencil-alt',
+          description: app.translator.trans('core.admin.nav.basics_text'),
+        },
+        app.translator.trans('core.admin.nav.basics_button')
+      )
     );
 
     items.add(
       'mail',
-      AdminLinkButton.component({
-        href: app.route('mail'),
-        icon: 'fas fa-envelope',
-        children: app.translator.trans('core.admin.nav.email_button'),
-        description: app.translator.trans('core.admin.nav.email_text'),
-      })
+      AdminLinkButton.component(
+        {
+          href: app.route('mail'),
+          icon: 'fas fa-envelope',
+          description: app.translator.trans('core.admin.nav.email_text'),
+        },
+        app.translator.trans('core.admin.nav.email_button')
+      )
     );
 
     items.add(
       'permissions',
-      AdminLinkButton.component({
-        href: app.route('permissions'),
-        icon: 'fas fa-key',
-        children: app.translator.trans('core.admin.nav.permissions_button'),
-        description: app.translator.trans('core.admin.nav.permissions_text'),
-      })
+      AdminLinkButton.component(
+        {
+          href: app.route('permissions'),
+          icon: 'fas fa-key',
+          description: app.translator.trans('core.admin.nav.permissions_text'),
+        },
+        app.translator.trans('core.admin.nav.permissions_button')
+      )
     );
 
     items.add(
       'appearance',
-      AdminLinkButton.component({
-        href: app.route('appearance'),
-        icon: 'fas fa-paint-brush',
-        children: app.translator.trans('core.admin.nav.appearance_button'),
-        description: app.translator.trans('core.admin.nav.appearance_text'),
-      })
+      AdminLinkButton.component(
+        {
+          href: app.route('appearance'),
+          icon: 'fas fa-paint-brush',
+          description: app.translator.trans('core.admin.nav.appearance_text'),
+        },
+        app.translator.trans('core.admin.nav.appearance_button')
+      )
     );
 
     items.add(
       'extensions',
-      AdminLinkButton.component({
-        href: app.route('extensions'),
-        icon: 'fas fa-puzzle-piece',
-        children: app.translator.trans('core.admin.nav.extensions_button'),
-        description: app.translator.trans('core.admin.nav.extensions_text'),
-      })
+      AdminLinkButton.component(
+        {
+          href: app.route('extensions'),
+          icon: 'fas fa-puzzle-piece',
+          description: app.translator.trans('core.admin.nav.extensions_text'),
+        },
+        app.translator.trans('core.admin.nav.extensions_button')
+      )
     );
 
     return items;

js/src/admin/components/AppearancePage.js

@@ -1,6 +1,7 @@
 import Page from '../../common/components/Page';
 import Button from '../../common/components/Button';
 import Switch from '../../common/components/Switch';
+import Stream from '../../common/utils/Stream';
 import EditCustomCssModal from './EditCustomCssModal';
 import EditCustomHeaderModal from './EditCustomHeaderModal';
 import EditCustomFooterModal from './EditCustomFooterModal';
@@ -8,13 +9,13 @@ import UploadImageButton from './UploadImageButton';
 import saveSettings from '../utils/saveSettings';
 
 export default class AppearancePage extends Page {
-  init() {
-    super.init();
+  oninit(vnode) {
+    super.oninit(vnode);
 
-    this.primaryColor = m.prop(app.data.settings.theme_primary_color);
-    this.secondaryColor = m.prop(app.data.settings.theme_secondary_color);
-    this.darkMode = m.prop(app.data.settings.theme_dark_mode);
-    this.coloredHeader = m.prop(app.data.settings.theme_colored_header);
+    this.primaryColor = Stream(app.data.settings.theme_primary_color);
+    this.secondaryColor = Stream(app.data.settings.theme_secondary_color);
+    this.darkMode = Stream(app.data.settings.theme_dark_mode);
+    this.coloredHeader = Stream(app.data.settings.theme_colored_header);
   }
 
   view() {
@@ -27,40 +28,34 @@ export default class AppearancePage extends Page {
               <div className="helpText">{app.translator.trans('core.admin.appearance.colors_text')}</div>
 
               <div className="AppearancePage-colors-input">
-                <input
-                  className="FormControl"
-                  type="text"
-                  placeholder="#aaaaaa"
-                  value={this.primaryColor()}
-                  onchange={m.withAttr('value', this.primaryColor)}
-                />
-                <input
-                  className="FormControl"
-                  type="text"
-                  placeholder="#aaaaaa"
-                  value={this.secondaryColor()}
-                  onchange={m.withAttr('value', this.secondaryColor)}
-                />
+                <input className="FormControl" type="text" placeholder="#aaaaaa" bidi={this.primaryColor} />
+                <input className="FormControl" type="text" placeholder="#aaaaaa" bidi={this.secondaryColor} />
               </div>
 
-              {Switch.component({
-                state: this.darkMode(),
-                children: app.translator.trans('core.admin.appearance.dark_mode_label'),
-                onchange: this.darkMode,
-              })}
+              {Switch.component(
+                {
+                  state: this.darkMode(),
+                  onchange: this.darkMode,
+                },
+                app.translator.trans('core.admin.appearance.dark_mode_label')
+              )}
 
-              {Switch.component({
-                state: this.coloredHeader(),
-                children: app.translator.trans('core.admin.appearance.colored_header_label'),
-                onchange: this.coloredHeader,
-              })}
+              {Switch.component(
+                {
+                  state: this.coloredHeader(),
+                  onchange: this.coloredHeader,
+                },
+                app.translator.trans('core.admin.appearance.colored_header_label')
+              )}
 
-              {Button.component({
-                className: 'Button Button--primary',
-                type: 'submit',
-                children: app.translator.trans('core.admin.appearance.submit_button'),
-                loading: this.loading,
-              })}
+              {Button.component(
+                {
+                  className: 'Button Button--primary',
+                  type: 'submit',
+                  loading: this.loading,
+                },
+                app.translator.trans('core.admin.appearance.submit_button')
+              )}
             </fieldset>
           </form>
 
@@ -79,31 +74,37 @@ export default class AppearancePage extends Page {
           <fieldset>
             <legend>{app.translator.trans('core.admin.appearance.custom_header_heading')}</legend>
             <div className="helpText">{app.translator.trans('core.admin.appearance.custom_header_text')}</div>
-            {Button.component({
-              className: 'Button',
-              children: app.translator.trans('core.admin.appearance.edit_header_button'),
-              onclick: () => app.modal.show(EditCustomHeaderModal),
-            })}
+            {Button.component(
+              {
+                className: 'Button',
+                onclick: () => app.modal.show(EditCustomHeaderModal),
+              },
+              app.translator.trans('core.admin.appearance.edit_header_button')
+            )}
           </fieldset>
 
           <fieldset>
             <legend>{app.translator.trans('core.admin.appearance.custom_footer_heading')}</legend>
             <div className="helpText">{app.translator.trans('core.admin.appearance.custom_footer_text')}</div>
-            {Button.component({
-              className: 'Button',
-              children: app.translator.trans('core.admin.appearance.edit_footer_button'),
-              onclick: () => app.modal.show(EditCustomFooterModal),
-            })}
+            {Button.component(
+              {
+                className: 'Button',
+                onclick: () => app.modal.show(EditCustomFooterModal),
+              },
+              app.translator.trans('core.admin.appearance.edit_footer_button')
+            )}
           </fieldset>
 
           <fieldset>
             <legend>{app.translator.trans('core.admin.appearance.custom_styles_heading')}</legend>
             <div className="helpText">{app.translator.trans('core.admin.appearance.custom_styles_text')}</div>
-            {Button.component({
-              className: 'Button',
-              children: app.translator.trans('core.admin.appearance.edit_css_button'),
-              onclick: () => app.modal.show(EditCustomCssModal),
-            })}
+            {Button.component(
+              {
+                className: 'Button',
+                onclick: () => app.modal.show(EditCustomCssModal),
+              },
+              app.translator.trans('core.admin.appearance.edit_css_button')
+            )}
           </fieldset>
         </div>
       </div>

js/src/admin/components/BasicsPage.js

@@ -5,10 +5,12 @@ import Button from '../../common/components/Button';
 import saveSettings from '../utils/saveSettings';
 import ItemList from '../../common/utils/ItemList';
 import Switch from '../../common/components/Switch';
+import Stream from '../../common/utils/Stream';
+import withAttr from '../../common/utils/withAttr';
 
 export default class BasicsPage extends Page {
-  init() {
-    super.init();
+  oninit(vnode) {
+    super.oninit(vnode);
 
     this.loading = false;
 
@@ -25,7 +27,7 @@ export default class BasicsPage extends Page {
     this.values = {};
 
     const settings = app.data.settings;
-    this.fields.forEach((key) => (this.values[key] = m.prop(settings[key])));
+    this.fields.forEach((key) => (this.values[key] = Stream(settings[key])));
 
     this.localeOptions = {};
     const locales = app.data.locales;
@@ -49,45 +51,51 @@ export default class BasicsPage extends Page {
       <div className="BasicsPage">
         <div className="container">
           <form onsubmit={this.onsubmit.bind(this)}>
-            {FieldSet.component({
-              label: app.translator.trans('core.admin.basics.forum_title_heading'),
-              children: [<input className="FormControl" value={this.values.forum_title()} oninput={m.withAttr('value', this.values.forum_title)} />],
-            })}
+            {FieldSet.component(
+              {
+                label: app.translator.trans('core.admin.basics.forum_title_heading'),
+              },
+              [<input className="FormControl" bidi={this.values.forum_title} />]
+            )}
 
-            {FieldSet.component({
-              label: app.translator.trans('core.admin.basics.forum_description_heading'),
-              children: [
+            {FieldSet.component(
+              {
+                label: app.translator.trans('core.admin.basics.forum_description_heading'),
+              },
+              [
                 <div className="helpText">{app.translator.trans('core.admin.basics.forum_description_text')}</div>,
-                <textarea
-                  className="FormControl"
-                  value={this.values.forum_description()}
-                  oninput={m.withAttr('value', this.values.forum_description)}
-                />,
-              ],
-            })}
+                <textarea className="FormControl" bidi={this.values.forum_description} />,
+              ]
+            )}
 
             {Object.keys(this.localeOptions).length > 1
-              ? FieldSet.component({
-                  label: app.translator.trans('core.admin.basics.default_language_heading'),
-                  children: [
+              ? FieldSet.component(
+                  {
+                    label: app.translator.trans('core.admin.basics.default_language_heading'),
+                  },
+                  [
                     Select.component({
                       options: this.localeOptions,
                       value: this.values.default_locale(),
                       onchange: this.values.default_locale,
                     }),
-                    Switch.component({
-                      state: this.values.show_language_selector(),
-                      onchange: this.values.show_language_selector,
-                      children: app.translator.trans('core.admin.basics.show_language_selector_label'),
-                    }),
-                  ],
-                })
+                    Switch.component(
+                      {
+                        state: this.values.show_language_selector(),
+                        onchange: this.values.show_language_selector,
+                      },
+                      app.translator.trans('core.admin.basics.show_language_selector_label')
+                    ),
+                  ]
+                )
               : ''}
 
-            {FieldSet.component({
-              label: app.translator.trans('core.admin.basics.home_page_heading'),
-              className: 'BasicsPage-homePage',
-              children: [
+            {FieldSet.component(
+              {
+                label: app.translator.trans('core.admin.basics.home_page_heading'),
+                className: 'BasicsPage-homePage',
+              },
+              [
                 <div className="helpText">{app.translator.trans('core.admin.basics.home_page_text')}</div>,
                 this.homePageItems()
                   .toArray()
@@ -98,51 +106,52 @@ export default class BasicsPage extends Page {
                         name="homePage"
                         value={path}
                         checked={this.values.default_route() === path}
-                        onclick={m.withAttr('value', this.values.default_route)}
+                        onclick={withAttr('value', this.values.default_route)}
                       />
                       {label}
                     </label>
                   )),
-              ],
-            })}
+              ]
+            )}
 
-            {FieldSet.component({
-              label: app.translator.trans('core.admin.basics.welcome_banner_heading'),
-              className: 'BasicsPage-welcomeBanner',
-              children: [
+            {FieldSet.component(
+              {
+                label: app.translator.trans('core.admin.basics.welcome_banner_heading'),
+                className: 'BasicsPage-welcomeBanner',
+              },
+              [
                 <div className="helpText">{app.translator.trans('core.admin.basics.welcome_banner_text')}</div>,
                 <div className="BasicsPage-welcomeBanner-input">
-                  <input className="FormControl" value={this.values.welcome_title()} oninput={m.withAttr('value', this.values.welcome_title)} />
-                  <textarea
-                    className="FormControl"
-                    value={this.values.welcome_message()}
-                    oninput={m.withAttr('value', this.values.welcome_message)}
-                  />
+                  <input className="FormControl" bidi={this.values.welcome_title} />
+                  <textarea className="FormControl" bidi={this.values.welcome_message} />
                 </div>,
-              ],
-            })}
+              ]
+            )}
 
             {Object.keys(this.displayNameOptions).length > 1
-              ? FieldSet.component({
-                  label: app.translator.trans('core.admin.basics.display_name_heading'),
-                  children: [
+              ? FieldSet.component(
+                  {
+                    label: app.translator.trans('core.admin.basics.display_name_heading'),
+                  },
+                  [
                     <div className="helpText">{app.translator.trans('core.admin.basics.display_name_text')}</div>,
                     Select.component({
                       options: this.displayNameOptions,
-                      value: this.values.display_name_driver(),
-                      onchange: this.values.display_name_driver,
+                      bidi: this.values.display_name_driver,
                     }),
-                  ],
-                })
+                  ]
+                )
               : ''}
 
-            {Button.component({
-              type: 'submit',
-              className: 'Button Button--primary',
-              children: app.translator.trans('core.admin.basics.submit_button'),
-              loading: this.loading,
-              disabled: !this.changed(),
-            })}
+            {Button.component(
+              {
+                type: 'submit',
+                className: 'Button Button--primary',
+                loading: this.loading,
+                disabled: !this.changed(),
+              },
+              app.translator.trans('core.admin.basics.submit_button')
+            )}
           </form>
         </div>
       </div>
@@ -185,10 +194,7 @@ export default class BasicsPage extends Page {
 
     saveSettings(settings)
       .then(() => {
-        this.successAlert = app.alerts.show({
-          type: 'success',
-          children: app.translator.trans('core.admin.basics.saved_message'),
-        });
+        this.successAlert = app.alerts.show({ type: 'success' }, app.translator.trans('core.admin.basics.saved_message'));
       })
       .catch(() => {})
       .then(() => {

js/src/admin/components/EditGroupModal.js

@@ -4,20 +4,23 @@ import Badge from '../../common/components/Badge';
 import Group from '../../common/models/Group';
 import ItemList from '../../common/utils/ItemList';
 import Switch from '../../common/components/Switch';
+import Stream from '../../common/utils/Stream';
 
 /**
  * The `EditGroupModal` component shows a modal dialog which allows the user
  * to create or edit a group.
  */
 export default class EditGroupModal extends Modal {
-  init() {
-    this.group = this.props.group || app.store.createRecord('groups');
+  oninit(vnode) {
+    super.oninit(vnode);
 
-    this.nameSingular = m.prop(this.group.nameSingular() || '');
-    this.namePlural = m.prop(this.group.namePlural() || '');
-    this.icon = m.prop(this.group.icon() || '');
-    this.color = m.prop(this.group.color() || '');
-    this.isHidden = m.prop(this.group.isHidden() || false);
+    this.group = this.attrs.group || app.store.createRecord('groups');
+
+    this.nameSingular = Stream(this.group.nameSingular() || '');
+    this.namePlural = Stream(this.group.namePlural() || '');
+    this.icon = Stream(this.group.icon() || '');
+    this.color = Stream(this.group.color() || '');
+    this.isHidden = Stream(this.group.isHidden() || false);
   }
 
   className() {
@@ -53,18 +56,8 @@ export default class EditGroupModal extends Modal {
       <div className="Form-group">
         <label>{app.translator.trans('core.admin.edit_group.name_label')}</label>
         <div className="EditGroupModal-name-input">
-          <input
-            className="FormControl"
-            placeholder={app.translator.trans('core.admin.edit_group.singular_placeholder')}
-            value={this.nameSingular()}
-            oninput={m.withAttr('value', this.nameSingular)}
-          />
-          <input
-            className="FormControl"
-            placeholder={app.translator.trans('core.admin.edit_group.plural_placeholder')}
-            value={this.namePlural()}
-            oninput={m.withAttr('value', this.namePlural)}
-          />
+          <input className="FormControl" placeholder={app.translator.trans('core.admin.edit_group.singular_placeholder')} bidi={this.nameSingular} />
+          <input className="FormControl" placeholder={app.translator.trans('core.admin.edit_group.plural_placeholder')} bidi={this.namePlural} />
         </div>
       </div>,
       30
@@ -74,7 +67,7 @@ export default class EditGroupModal extends Modal {
       'color',
       <div className="Form-group">
         <label>{app.translator.trans('core.admin.edit_group.color_label')}</label>
-        <input className="FormControl" placeholder="#aaaaaa" value={this.color()} oninput={m.withAttr('value', this.color)} />
+        <input className="FormControl" placeholder="#aaaaaa" bidi={this.color} />
       </div>,
       20
     );
@@ -86,7 +79,7 @@ export default class EditGroupModal extends Modal {
         <div className="helpText">
           {app.translator.trans('core.admin.edit_group.icon_text', { a: <a href="https://fontawesome.com/icons?m=free" tabindex="-1" /> })}
         </div>
-        <input className="FormControl" placeholder="fas fa-bolt" value={this.icon()} oninput={m.withAttr('value', this.icon)} />
+        <input className="FormControl" placeholder="fas fa-bolt" bidi={this.icon} />
       </div>,
       10
     );
@@ -94,11 +87,13 @@ export default class EditGroupModal extends Modal {
     items.add(
       'hidden',
       <div className="Form-group">
-        {Switch.component({
-          state: !!Number(this.isHidden()),
-          children: app.translator.trans('core.admin.edit_group.hide_label'),
-          onchange: this.isHidden,
-        })}
+        {Switch.component(
+          {
+            state: !!Number(this.isHidden()),
+            onchange: this.isHidden,
+          },
+          app.translator.trans('core.admin.edit_group.hide_label')
+        )}
       </div>,
       10
     );
@@ -106,12 +101,14 @@ export default class EditGroupModal extends Modal {
     items.add(
       'submit',
       <div className="Form-group">
-        {Button.component({
-          type: 'submit',
-          className: 'Button Button--primary EditGroupModal-save',
-          loading: this.loading,
-          children: app.translator.trans('core.admin.edit_group.submit_button'),
-        })}
+        {Button.component(
+          {
+            type: 'submit',
+            className: 'Button Button--primary EditGroupModal-save',
+            loading: this.loading,
+          },
+          app.translator.trans('core.admin.edit_group.submit_button')
+        )}
         {this.group.exists && this.group.id() !== Group.ADMINISTRATOR_ID ? (
           <button type="button" className="Button EditGroupModal-delete" onclick={this.deleteGroup.bind(this)}>
             {app.translator.trans('core.admin.edit_group.delete_button')}

js/src/admin/components/ExtensionsPage.js

@@ -12,12 +12,14 @@ export default class ExtensionsPage extends Page {
       <div className="ExtensionsPage">
         <div className="ExtensionsPage-header">
           <div className="container">
-            {Button.component({
-              children: app.translator.trans('core.admin.extensions.add_button'),
-              icon: 'fas fa-plus',
-              className: 'Button Button--primary',
-              onclick: () => app.modal.show(AddExtensionModal),
-            })}
+            {Button.component(
+              {
+                icon: 'fas fa-plus',
+                className: 'Button Button--primary',
+                onclick: () => app.modal.show(AddExtensionModal),
+              },
+              app.translator.trans('core.admin.extensions.add_button')
+            )}
           </div>
         </div>
 
@@ -72,31 +74,35 @@ export default class ExtensionsPage extends Page {
     if (app.extensionSettings[name]) {
       items.add(
         'settings',
-        Button.component({
-          icon: 'fas fa-cog',
-          children: app.translator.trans('core.admin.extensions.settings_button'),
-          onclick: app.extensionSettings[name],
-        })
+        Button.component(
+          {
+            icon: 'fas fa-cog',
+            onclick: app.extensionSettings[name],
+          },
+          app.translator.trans('core.admin.extensions.settings_button')
+        )
       );
     }
 
     if (!enabled) {
       items.add(
         'uninstall',
-        Button.component({
-          icon: 'far fa-trash-alt',
-          children: app.translator.trans('core.admin.extensions.uninstall_button'),
-          onclick: () => {
-            app
-              .request({
-                url: app.forum.attribute('apiUrl') + '/extensions/' + name,
-                method: 'DELETE',
-              })
-              .then(() => window.location.reload());
+        Button.component(
+          {
+            icon: 'far fa-trash-alt',
+            onclick: () => {
+              app
+                .request({
+                  url: app.forum.attribute('apiUrl') + '/extensions/' + name,
+                  method: 'DELETE',
+                })
+                .then(() => window.location.reload());
 
-            app.modal.show(LoadingModal);
+              app.modal.show(LoadingModal);
+            },
           },
-        })
+          app.translator.trans('core.admin.extensions.uninstall_button')
+        )
       );
     }
 
@@ -116,7 +122,8 @@ export default class ExtensionsPage extends Page {
       .request({
         url: app.forum.attribute('apiUrl') + '/extensions/' + id,
         method: 'PATCH',
-        data: { enabled: !enabled },
+        body: { enabled: !enabled },
+        errorHandler: this.onerror.bind(this),
       })
       .then(() => {
         if (!enabled) localStorage.setItem('enabledExtension', id);
@@ -125,4 +132,27 @@ export default class ExtensionsPage extends Page {
 
     app.modal.show(LoadingModal);
   }
+
+  onerror(e) {
+    // We need to give the modal animation time to start; if we close the modal too early,
+    // it breaks the bootstrap modal library.
+    // TODO: This workaround should be removed when we move away from bootstrap JS for modals.
+    setTimeout(() => {
+      app.modal.close();
+    }, 300); // Bootstrap's Modal.TRANSITION_DURATION is 300 ms.
+
+    if (e.status !== 409) {
+      throw e;
+    }
+
+    const error = e.response.errors[0];
+
+    app.alerts.show(
+      { type: 'error' },
+      app.translator.trans(`core.lib.error.${error.code}_message`, {
+        extension: error.extension,
+        extensions: error.extensions.join(', '),
+      })
+    );
+  }
 }

js/src/admin/components/HeaderSecondary.js

@@ -11,13 +11,6 @@ export default class HeaderSecondary extends Component {
     return <ul className="Header-controls">{listItems(this.items().toArray())}</ul>;
   }
 
-  config(isInitialized, context) {
-    // Since this component is 'above' the content of the page (that is, it is a
-    // part of the global UI that persists between routes), we will flag the DOM
-    // to be retained across route changes.
-    context.retain = true;
-  }
-
   /**
    * Build an item list for the controls.
    *

js/src/admin/components/MailPage.js

@@ -5,10 +5,11 @@ import Alert from '../../common/components/Alert';
 import Select from '../../common/components/Select';
 import LoadingIndicator from '../../common/components/LoadingIndicator';
 import saveSettings from '../utils/saveSettings';
+import Stream from '../../common/utils/Stream';
 
 export default class MailPage extends Page {
-  init() {
-    super.init();
+  oninit(vnode) {
+    super.oninit(vnode);
 
     this.saving = false;
     this.sendingTest = false;
@@ -24,7 +25,7 @@ export default class MailPage extends Page {
     this.status = { sending: false, errors: {} };
 
     const settings = app.data.settings;
-    this.fields.forEach((key) => (this.values[key] = m.prop(settings[key])));
+    this.fields.forEach((key) => (this.values[key] = Stream(settings[key])));
 
     app
       .request({
@@ -39,7 +40,7 @@ export default class MailPage extends Page {
         for (const driver in this.driverFields) {
           for (const field in this.driverFields[driver]) {
             this.fields.push(field);
-            this.values[field] = m.prop(settings[field]);
+            this.values[field] = Stream(settings[field]);
           }
         }
 
@@ -69,23 +70,27 @@ export default class MailPage extends Page {
             <h2>{app.translator.trans('core.admin.email.heading')}</h2>
             <div className="helpText">{app.translator.trans('core.admin.email.text')}</div>
 
-            {FieldSet.component({
-              label: app.translator.trans('core.admin.email.addresses_heading'),
-              className: 'MailPage-MailSettings',
-              children: [
+            {FieldSet.component(
+              {
+                label: app.translator.trans('core.admin.email.addresses_heading'),
+                className: 'MailPage-MailSettings',
+              },
+              [
                 <div className="MailPage-MailSettings-input">
                   <label>
                     {app.translator.trans('core.admin.email.from_label')}
-                    <input className="FormControl" value={this.values.mail_from() || ''} oninput={m.withAttr('value', this.values.mail_from)} />
+                    <input className="FormControl" bidi={this.values.mail_from} />
                   </label>
                 </div>,
-              ],
-            })}
+              ]
+            )}
 
-            {FieldSet.component({
-              label: app.translator.trans('core.admin.email.driver_heading'),
-              className: 'MailPage-MailSettings',
-              children: [
+            {FieldSet.component(
+              {
+                label: app.translator.trans('core.admin.email.driver_heading'),
+                className: 'MailPage-MailSettings',
+              },
+              [
                 <div className="MailPage-MailSettings-input">
                   <label>
                     {app.translator.trans('core.admin.email.driver_label')}
@@ -96,20 +101,24 @@ export default class MailPage extends Page {
                     />
                   </label>
                 </div>,
-              ],
-            })}
+              ]
+            )}
 
             {this.status.sending ||
-              Alert.component({
-                children: app.translator.trans('core.admin.email.not_sending_message'),
-                dismissible: false,
-              })}
+              Alert.component(
+                {
+                  dismissible: false,
+                },
+                app.translator.trans('core.admin.email.not_sending_message')
+              )}
 
             {fieldKeys.length > 0 &&
-              FieldSet.component({
-                label: app.translator.trans(`core.admin.email.${this.values.mail_driver()}_heading`),
-                className: 'MailPage-MailSettings',
-                children: [
+              FieldSet.component(
+                {
+                  label: app.translator.trans(`core.admin.email.${this.values.mail_driver()}_heading`),
+                  className: 'MailPage-MailSettings',
+                },
+                [
                   <div className="MailPage-MailSettings-input">
                     {fieldKeys.map((field) => [
                       <label>
@@ -119,31 +128,37 @@ export default class MailPage extends Page {
                       this.status.errors[field] && <p className="ValidationError">{this.status.errors[field]}</p>,
                     ])}
                   </div>,
-                ],
-              })}
+                ]
+              )}
 
             <FieldSet>
-              {Button.component({
-                type: 'submit',
-                className: 'Button Button--primary',
-                children: app.translator.trans('core.admin.email.submit_button'),
-                disabled: !this.changed(),
-              })}
+              {Button.component(
+                {
+                  type: 'submit',
+                  className: 'Button Button--primary',
+                  disabled: !this.changed(),
+                },
+                app.translator.trans('core.admin.email.submit_button')
+              )}
             </FieldSet>
 
-            {FieldSet.component({
-              label: app.translator.trans('core.admin.email.send_test_mail_heading'),
-              className: 'MailPage-MailSettings',
-              children: [
+            {FieldSet.component(
+              {
+                label: app.translator.trans('core.admin.email.send_test_mail_heading'),
+                className: 'MailPage-MailSettings',
+              },
+              [
                 <div className="helpText">{app.translator.trans('core.admin.email.send_test_mail_text', { email: app.session.user.email() })}</div>,
-                Button.component({
-                  className: 'Button Button--primary',
-                  children: app.translator.trans('core.admin.email.send_test_mail_button'),
-                  disabled: this.sendingTest || this.changed(),
-                  onclick: () => this.sendTestEmail(),
-                }),
-              ],
-            })}
+                Button.component(
+                  {
+                    className: 'Button Button--primary',
+                    disabled: this.sendingTest || this.changed(),
+                    onclick: () => this.sendTestEmail(),
+                  },
+                  app.translator.trans('core.admin.email.send_test_mail_button')
+                ),
+              ]
+            )}
           </form>
         </div>
       </div>
@@ -156,7 +171,7 @@ export default class MailPage extends Page {
     const prop = this.values[name];
 
     if (typeof field === 'string') {
-      return <input className="FormControl" value={prop() || ''} oninput={m.withAttr('value', prop)} />;
+      return <input className="FormControl" bidi={prop} />;
     } else {
       return <Select value={prop()} options={field} onchange={prop} />;
     }
@@ -179,10 +194,7 @@ export default class MailPage extends Page {
       })
       .then((response) => {
         this.sendingTest = false;
-        this.testEmailSuccessAlert = app.alerts.show({
-          type: 'success',
-          children: app.translator.trans('core.admin.email.send_test_mail_success'),
-        });
+        this.testEmailSuccessAlert = app.alerts.show({ type: 'success' }, app.translator.trans('core.admin.email.send_test_mail_success'));
       })
       .catch((error) => {
         this.sendingTest = false;
@@ -205,10 +217,7 @@ export default class MailPage extends Page {
 
     saveSettings(settings)
       .then(() => {
-        this.successAlert = app.alerts.show({
-          type: 'success',
-          children: app.translator.trans('core.admin.basics.saved_message'),
-        });
+        this.successAlert = app.alerts.show({ type: 'success' }, app.translator.trans('core.admin.basics.saved_message'));
       })
       .catch(() => {})
       .then(() => {

js/src/admin/components/PermissionDropdown.js

@@ -32,101 +32,109 @@ function filterByRequiredPermissions(groupIds, permission) {
 }
 
 export default class PermissionDropdown extends Dropdown {
-  static initProps(props) {
-    super.initProps(props);
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
 
-    props.className = 'PermissionDropdown';
-    props.buttonClassName = 'Button Button--text';
+    attrs.className = 'PermissionDropdown';
+    attrs.buttonClassName = 'Button Button--text';
   }
 
-  view() {
-    this.props.children = [];
+  view(vnode) {
+    const children = [];
 
-    let groupIds = app.data.permissions[this.props.permission] || [];
+    let groupIds = app.data.permissions[this.attrs.permission] || [];
 
-    groupIds = filterByRequiredPermissions(groupIds, this.props.permission);
+    groupIds = filterByRequiredPermissions(groupIds, this.attrs.permission);
 
     const everyone = groupIds.indexOf(Group.GUEST_ID) !== -1;
     const members = groupIds.indexOf(Group.MEMBER_ID) !== -1;
     const adminGroup = app.store.getById('groups', Group.ADMINISTRATOR_ID);
 
     if (everyone) {
-      this.props.label = Badge.component({ icon: 'fas fa-globe' });
+      this.attrs.label = Badge.component({ icon: 'fas fa-globe' });
     } else if (members) {
-      this.props.label = Badge.component({ icon: 'fas fa-user' });
+      this.attrs.label = Badge.component({ icon: 'fas fa-user' });
     } else {
-      this.props.label = [badgeForId(Group.ADMINISTRATOR_ID), groupIds.map(badgeForId)];
+      this.attrs.label = [badgeForId(Group.ADMINISTRATOR_ID), groupIds.map(badgeForId)];
     }
 
     if (this.showing) {
-      if (this.props.allowGuest) {
-        this.props.children.push(
-          Button.component({
-            children: [Badge.component({ icon: 'fas fa-globe' }), ' ', app.translator.trans('core.admin.permissions_controls.everyone_button')],
-            icon: everyone ? 'fas fa-check' : true,
-            onclick: () => this.save([Group.GUEST_ID]),
-            disabled: this.isGroupDisabled(Group.GUEST_ID),
-          })
+      if (this.attrs.allowGuest) {
+        children.push(
+          Button.component(
+            {
+              icon: everyone ? 'fas fa-check' : true,
+              onclick: () => this.save([Group.GUEST_ID]),
+              disabled: this.isGroupDisabled(Group.GUEST_ID),
+            },
+            [Badge.component({ icon: 'fas fa-globe' }), ' ', app.translator.trans('core.admin.permissions_controls.everyone_button')]
+          )
         );
       }
 
-      this.props.children.push(
-        Button.component({
-          children: [Badge.component({ icon: 'fas fa-user' }), ' ', app.translator.trans('core.admin.permissions_controls.members_button')],
-          icon: members ? 'fas fa-check' : true,
-          onclick: () => this.save([Group.MEMBER_ID]),
-          disabled: this.isGroupDisabled(Group.MEMBER_ID),
-        }),
+      children.push(
+        Button.component(
+          {
+            icon: members ? 'fas fa-check' : true,
+            onclick: () => this.save([Group.MEMBER_ID]),
+            disabled: this.isGroupDisabled(Group.MEMBER_ID),
+          },
+          [Badge.component({ icon: 'fas fa-user' }), ' ', app.translator.trans('core.admin.permissions_controls.members_button')]
+        ),
 
         Separator.component(),
 
-        Button.component({
-          children: [badgeForId(adminGroup.id()), ' ', adminGroup.namePlural()],
-          icon: !everyone && !members ? 'fas fa-check' : true,
-          disabled: !everyone && !members,
-          onclick: (e) => {
-            if (e.shiftKey) e.stopPropagation();
-            this.save([]);
+        Button.component(
+          {
+            icon: !everyone && !members ? 'fas fa-check' : true,
+            disabled: !everyone && !members,
+            onclick: (e) => {
+              if (e.shiftKey) e.stopPropagation();
+              this.save([]);
+            },
           },
-        })
+          [badgeForId(adminGroup.id()), ' ', adminGroup.namePlural()]
+        )
       );
 
       [].push.apply(
-        this.props.children,
+        children,
         app.store
           .all('groups')
           .filter((group) => [Group.ADMINISTRATOR_ID, Group.GUEST_ID, Group.MEMBER_ID].indexOf(group.id()) === -1)
           .map((group) =>
-            Button.component({
-              children: [badgeForId(group.id()), ' ', group.namePlural()],
-              icon: groupIds.indexOf(group.id()) !== -1 ? 'fas fa-check' : true,
-              onclick: (e) => {
-                if (e.shiftKey) e.stopPropagation();
-                this.toggle(group.id());
+            Button.component(
+              {
+                icon: groupIds.indexOf(group.id()) !== -1 ? 'fas fa-check' : true,
+                onclick: (e) => {
+                  if (e.shiftKey) e.stopPropagation();
+                  this.toggle(group.id());
+                },
+                disabled: this.isGroupDisabled(group.id()) && this.isGroupDisabled(Group.MEMBER_ID) && this.isGroupDisabled(Group.GUEST_ID),
               },
-              disabled: this.isGroupDisabled(group.id()) && this.isGroupDisabled(Group.MEMBER_ID) && this.isGroupDisabled(Group.GUEST_ID),
-            })
+              [badgeForId(group.id()), ' ', group.namePlural()]
+            )
           )
       );
     }
 
-    return super.view();
+    return super.view({ ...vnode, children });
   }
 
   save(groupIds) {
-    const permission = this.props.permission;
+    const permission = this.attrs.permission;
 
     app.data.permissions[permission] = groupIds;
 
     app.request({
       method: 'POST',
       url: app.forum.attribute('apiUrl') + '/permission',
-      data: { permission, groupIds },
+      body: { permission, groupIds },
     });
   }
 
   toggle(groupId) {
-    const permission = this.props.permission;
+    const permission = this.attrs.permission;
 
     let groupIds = app.data.permissions[permission] || [];
 
@@ -143,6 +151,6 @@ export default class PermissionDropdown extends Dropdown {
   }
 
   isGroupDisabled(id) {
-    return filterByRequiredPermissions([id], this.props.permission).indexOf(id) === -1;
+    return filterByRequiredPermissions([id], this.attrs.permission).indexOf(id) === -1;
   }
 }

js/src/admin/components/PermissionGrid.js

@@ -6,7 +6,9 @@ import ItemList from '../../common/utils/ItemList';
 import icon from '../../common/helpers/icon';
 
 export default class PermissionGrid extends Component {
-  init() {
+  oninit(vnode) {
+    super.oninit(vnode);
+
     this.permissions = this.permissionItems().toArray();
   }
 

js/src/admin/components/SessionDropdown.js

@@ -9,18 +9,16 @@ import ItemList from '../../common/utils/ItemList';
  * avatar/name, with a dropdown of session controls.
  */
 export default class SessionDropdown extends Dropdown {
-  static initProps(props) {
-    super.initProps(props);
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
 
-    props.className = 'SessionDropdown';
-    props.buttonClassName = 'Button Button--user Button--flat';
-    props.menuClassName = 'Dropdown-menu--right';
+    attrs.className = 'SessionDropdown';
+    attrs.buttonClassName = 'Button Button--user Button--flat';
+    attrs.menuClassName = 'Dropdown-menu--right';
   }
 
-  view() {
-    this.props.children = this.items().toArray();
-
-    return super.view();
+  view(vnode) {
+    return super.view({ ...vnode, children: this.items().toArray() });
   }
 
   getButtonContent() {
@@ -39,11 +37,13 @@ export default class SessionDropdown extends Dropdown {
 
     items.add(
       'logOut',
-      Button.component({
-        icon: 'fas fa-sign-out-alt',
-        children: app.translator.trans('core.admin.header.log_out_button'),
-        onclick: app.session.logout.bind(app.session),
-      }),
+      Button.component(
+        {
+          icon: 'fas fa-sign-out-alt',
+          onclick: app.session.logout.bind(app.session),
+        },
+        app.translator.trans('core.admin.header.log_out_button')
+      ),
       -100
     );
 

js/src/admin/components/SettingDropdown.js

@@ -3,23 +3,30 @@ import Button from '../../common/components/Button';
 import saveSettings from '../utils/saveSettings';
 
 export default class SettingDropdown extends SelectDropdown {
-  static initProps(props) {
-    super.initProps(props);
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
 
-    props.className = 'SettingDropdown';
-    props.buttonClassName = 'Button Button--text';
-    props.caretIcon = 'fas fa-caret-down';
-    props.defaultLabel = 'Custom';
+    attrs.className = 'SettingDropdown';
+    attrs.buttonClassName = 'Button Button--text';
+    attrs.caretIcon = 'fas fa-caret-down';
+    attrs.defaultLabel = 'Custom';
+  }
 
-    props.children = props.options.map(({ value, label }) => {
-      const active = app.data.settings[props.key] === value;
+  view(vnode) {
+    return super.view({
+      ...vnode,
+      children: this.attrs.options.map(({ value, label }) => {
+        const active = app.data.settings[this.attrs.key] === value;
 
-      return Button.component({
-        children: label,
-        icon: active ? 'fas fa-check' : true,
-        onclick: saveSettings.bind(this, { [props.key]: value }),
-        active,
-      });
+        return Button.component(
+          {
+            icon: active ? 'fas fa-check' : true,
+            onclick: saveSettings.bind(this, { [this.attrs.key]: value }),
+            active,
+          },
+          label
+        );
+      }),
     });
   }
 }

js/src/admin/components/SettingsModal.js

@@ -1,9 +1,12 @@
 import Modal from '../../common/components/Modal';
 import Button from '../../common/components/Button';
+import Stream from '../../common/utils/Stream';
 import saveSettings from '../utils/saveSettings';
 
 export default class SettingsModal extends Modal {
-  init() {
+  oninit(vnode) {
+    super.oninit(vnode);
+
     this.settings = {};
     this.loading = false;
   }
@@ -33,7 +36,7 @@ export default class SettingsModal extends Modal {
   }
 
   setting(key, fallback = '') {
-    this.settings[key] = this.settings[key] || m.prop(app.data.settings[key] || fallback);
+    this.settings[key] = this.settings[key] || Stream(app.data.settings[key] || fallback);
 
     return this.settings[key];
   }

js/src/admin/components/UploadImageButton.js

@@ -1,32 +1,28 @@
 import Button from '../../common/components/Button';
 
 export default class UploadImageButton extends Button {
-  init() {
-    this.loading = false;
-  }
+  loading = false;
 
-  view() {
-    this.props.loading = this.loading;
-    this.props.className = (this.props.className || '') + ' Button';
+  view(vnode) {
+    this.attrs.loading = this.loading;
+    this.attrs.className = (this.attrs.className || '') + ' Button';
 
-    if (app.data.settings[this.props.name + '_path']) {
-      this.props.onclick = this.remove.bind(this);
-      this.props.children = app.translator.trans('core.admin.upload_image.remove_button');
+    if (app.data.settings[this.attrs.name + '_path']) {
+      this.attrs.onclick = this.remove.bind(this);
 
       return (
         <div>
           <p>
-            <img src={app.forum.attribute(this.props.name + 'Url')} alt="" />
+            <img src={app.forum.attribute(this.attrs.name + 'Url')} alt="" />
           </p>
-          <p>{super.view()}</p>
+          <p>{super.view({ ...vnode, children: app.translator.trans('core.admin.upload_image.remove_button') })}</p>
         </div>
       );
     } else {
-      this.props.onclick = this.upload.bind(this);
-      this.props.children = app.translator.trans('core.admin.upload_image.upload_button');
+      this.attrs.onclick = this.upload.bind(this);
     }
 
-    return super.view();
+    return super.view({ ...vnode, children: app.translator.trans('core.admin.upload_image.upload_button') });
   }
 
   /**
@@ -42,8 +38,8 @@ export default class UploadImageButton extends Button {
       .hide()
       .click()
       .on('change', (e) => {
-        const data = new FormData();
-        data.append(this.props.name, $(e.target)[0].files[0]);
+        const body = new FormData();
+        body.append(this.attrs.name, $(e.target)[0].files[0]);
 
         this.loading = true;
         m.redraw();
@@ -53,7 +49,7 @@ export default class UploadImageButton extends Button {
             method: 'POST',
             url: this.resourceUrl(),
             serialize: (raw) => raw,
-            data,
+            body,
           })
           .then(this.success.bind(this), this.failure.bind(this));
       });
@@ -75,7 +71,7 @@ export default class UploadImageButton extends Button {
   }
 
   resourceUrl() {
-    return app.forum.attribute('apiUrl') + '/' + this.props.name;
+    return app.forum.attribute('apiUrl') + '/' + this.attrs.name;
   }
 
   /**

js/src/admin/routes.js

@@ -12,11 +12,11 @@ import MailPage from './components/MailPage';
  */
 export default function (app) {
   app.routes = {
-    dashboard: { path: '/', component: DashboardPage.component() },
-    basics: { path: '/basics', component: BasicsPage.component() },
-    permissions: { path: '/permissions', component: PermissionsPage.component() },
-    appearance: { path: '/appearance', component: AppearancePage.component() },
-    extensions: { path: '/extensions', component: ExtensionsPage.component() },
-    mail: { path: '/mail', component: MailPage.component() },
+    dashboard: { path: '/', component: DashboardPage },
+    basics: { path: '/basics', component: BasicsPage },
+    permissions: { path: '/permissions', component: PermissionsPage },
+    appearance: { path: '/appearance', component: AppearancePage },
+    extensions: { path: '/extensions', component: ExtensionsPage },
+    mail: { path: '/mail', component: MailPage },
   };
 }

js/src/admin/utils/saveSettings.js

@@ -7,7 +7,7 @@ export default function saveSettings(settings) {
     .request({
       method: 'POST',
       url: app.forum.attribute('apiUrl') + '/settings',
-      data: settings,
+      body: settings,
     })
     .catch((error) => {
       app.data.settings = oldSettings;

js/src/common/Application.js

@@ -189,21 +189,28 @@ export default class Application {
   }
 
   mount(basePath = '') {
-    m.mount(document.getElementById('modal'), <ModalManager state={this.modal} />);
-    m.mount(document.getElementById('alerts'), <AlertManager state={this.alerts} />);
+    // An object with a callable view property is used in order to pass arguments to the component; see https://mithril.js.org/mount.html
+    m.mount(document.getElementById('modal'), { view: () => ModalManager.component({ state: this.modal }) });
+    m.mount(document.getElementById('alerts'), { view: () => AlertManager.component({ state: this.alerts }) });
 
     this.drawer = new Drawer();
 
     m.route(document.getElementById('content'), basePath + '/', mapRoutes(this.routes, basePath));
 
     // Add a class to the body which indicates that the page has been scrolled
-    // down.
-    new ScrollListener((top) => {
+    // down. When this happens, we'll add classes to the header and app body
+    // which will set the navbar's position to fixed. We don't want to always
+    // have it fixed, as that could overlap with custom headers.
+    const scrollListener = new ScrollListener((top) => {
       const $app = $('#app');
       const offset = $app.offset().top;
 
       $app.toggleClass('affix', top >= offset).toggleClass('scrolled', top > offset);
-    }).start();
+      $('.App-header').toggleClass('navbar-fixed-top', top >= offset);
+    });
+
+    scrollListener.start();
+    scrollListener.update();
 
     $(() => {
       $('body').addClass('ontouchstart' in window ? 'touch' : 'no-touch');
@@ -263,7 +270,7 @@ export default class Application {
 
   updateTitle() {
     const count = this.titleCount ? `(${this.titleCount}) ` : '';
-    const pageTitleWithSeparator = this.title && m.route() !== '/' ? this.title + ' - ' : '';
+    const pageTitleWithSeparator = this.title && m.route.get() !== '/' ? this.title + ' - ' : '';
     const title = this.forum.attribute('title');
     document.title = count + pageTitleWithSeparator + title;
   }
@@ -271,7 +278,7 @@ export default class Application {
   /**
    * Make an AJAX request, handling any low-level errors that may occur.
    *
-   * @see https://lhorie.github.io/mithril/mithril.request.html
+   * @see https://mithril.js.org/request.html
    * @param {Object} options
    * @return {Promise}
    * @public
@@ -342,16 +349,14 @@ export default class Application {
 
     // Now make the request. If it's a failure, inspect the error that was
     // returned and show an alert containing its contents.
-    const deferred = m.deferred();
-
-    m.request(options).then(
-      (response) => deferred.resolve(response),
+    return m.request(options).then(
+      (response) => response,
       (error) => {
-        let children;
+        let content;
 
         switch (error.status) {
           case 422:
-            children = error.response.errors
+            content = error.response.errors
               .map((error) => [error.detail, <br />])
               .reduce((a, b) => a.concat(b), [])
               .slice(0, -1);
@@ -359,30 +364,31 @@ export default class Application {
 
           case 401:
           case 403:
-            children = app.translator.trans('core.lib.error.permission_denied_message');
+            content = app.translator.trans('core.lib.error.permission_denied_message');
             break;
 
           case 404:
           case 410:
-            children = app.translator.trans('core.lib.error.not_found_message');
+            content = app.translator.trans('core.lib.error.not_found_message');
             break;
 
           case 429:
-            children = app.translator.trans('core.lib.error.rate_limit_exceeded_message');
+            content = app.translator.trans('core.lib.error.rate_limit_exceeded_message');
             break;
 
           default:
-            children = app.translator.trans('core.lib.error.generic_message');
+            content = app.translator.trans('core.lib.error.generic_message');
         }
 
         const isDebug = app.forum.attribute('debug');
         // contains a formatted errors if possible, response must be an JSON API array of errors
         // the details property is decoded to transform escaped characters such as '\n'
-        const formattedError = error.response && Array.isArray(error.response.errors) && error.response.errors.map((e) => decodeURI(e.detail));
+        const errors = error.response && error.response.errors;
+        const formattedError = Array.isArray(errors) && errors[0] && errors[0].detail && errors.map((e) => decodeURI(e.detail));
 
         error.alert = {
           type: 'error',
-          children,
+          content,
           controls: isDebug && [
             <Button className="Button Button--link" onclick={this.showDebug.bind(this, error, formattedError)}>
               Debug
@@ -404,14 +410,12 @@ export default class Application {
             console.groupEnd();
           }
 
-          this.requestErrorAlert = this.alerts.show(error.alert);
+          this.requestErrorAlert = this.alerts.show(error.alert, error.alert.content);
         }
 
-        deferred.reject(error);
+        return Promise.reject(error);
       }
     );
-
-    return deferred.promise;
   }
 
   /**
@@ -434,9 +438,19 @@ export default class Application {
    * @public
    */
   route(name, params = {}) {
-    const url = this.routes[name].path.replace(/:([^\/]+)/g, (m, key) => extract(params, key));
-    const queryString = m.route.buildQueryString(params);
-    const prefix = m.route.mode === 'pathname' ? app.forum.attribute('basePath') : '';
+    const route = this.routes[name];
+
+    if (!route) throw new Error(`Route '${name}' does not exist`);
+
+    const url = route.path.replace(/:([^\/]+)/g, (m, key) => extract(params, key));
+
+    // Remove falsy values in params to avoid having urls like '/?sort&q'
+    for (const key in params) {
+      if (params.hasOwnProperty(key) && !params[key]) delete params[key];
+    }
+
+    const queryString = m.buildQueryString(params);
+    const prefix = m.route.prefix === '' ? this.forum.attribute('basePath') : '';
 
     return prefix + url + (queryString ? '?' + queryString : '');
   }

js/src/common/Component.js

@@ -1,221 +0,0 @@
-/*
- * This file is part of Flarum.
- *
- * (c) Toby Zerner <toby.zerner@gmail.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
-/**
- * The `Component` class defines a user interface 'building block'. A component
- * can generate a virtual DOM to be rendered on each redraw.
- *
- * An instance's virtual DOM can be retrieved directly using the {@link
- * Component#render} method.
- *
- * @example
- * this.myComponentInstance = new MyComponent({foo: 'bar'});
- * return m('div', this.myComponentInstance.render());
- *
- * Alternatively, components can be nested, letting Mithril take care of
- * instance persistence. For this, the static {@link Component.component} method
- * can be used.
- *
- * @example
- * return m('div', MyComponent.component({foo: 'bar'));
- *
- * @see https://lhorie.github.io/mithril/mithril.component.html
- * @abstract
- */
-export default class Component {
-  /**
-   * @param {Object} props
-   * @param {Array|Object} children
-   * @public
-   */
-  constructor(props = {}, children = null) {
-    if (children) props.children = children;
-
-    this.constructor.initProps(props);
-
-    /**
-     * The properties passed into the component.
-     *
-     * @type {Object}
-     */
-    this.props = props;
-
-    /**
-     * The root DOM element for the component.
-     *
-     * @type DOMElement
-     * @public
-     */
-    this.element = null;
-
-    /**
-     * Whether or not to retain the component's subtree on redraw.
-     *
-     * @type {boolean}
-     * @public
-     */
-    this.retain = false;
-
-    this.init();
-  }
-
-  /**
-   * Called when the component is constructed.
-   *
-   * @protected
-   */
-  init() {}
-
-  /**
-   * Called when the component is destroyed, i.e. after a redraw where it is no
-   * longer a part of the view.
-   *
-   * @see https://lhorie.github.io/mithril/mithril.component.html#unloading-components
-   * @param {Object} e
-   * @public
-   */
-  onunload() {}
-
-  /**
-   * Get the renderable virtual DOM that represents the component's view.
-   *
-   * This should NOT be overridden by subclasses. Subclasses wishing to define
-   * their virtual DOM should override Component#view instead.
-   *
-   * @example
-   * this.myComponentInstance = new MyComponent({foo: 'bar'});
-   * return m('div', this.myComponentInstance.render());
-   *
-   * @returns {Object}
-   * @final
-   * @public
-   */
-  render() {
-    const vdom = this.retain ? { subtree: 'retain' } : this.view();
-
-    // Override the root element's config attribute with our own function, which
-    // will set the component instance's element property to the root DOM
-    // element, and then run the component class' config method.
-    vdom.attrs = vdom.attrs || {};
-
-    const originalConfig = vdom.attrs.config;
-
-    vdom.attrs.config = (...args) => {
-      this.element = args[0];
-      this.config.apply(this, args.slice(1));
-      if (originalConfig) originalConfig.apply(this, args);
-    };
-
-    return vdom;
-  }
-
-  /**
-   * Returns a jQuery object for this component's element. If you pass in a
-   * selector string, this method will return a jQuery object, using the current
-   * element as its buffer.
-   *
-   * For example, calling `component.$('li')` will return a jQuery object
-   * containing all of the `li` elements inside the DOM element of this
-   * component.
-   *
-   * @param {String} [selector] a jQuery-compatible selector string
-   * @returns {jQuery} the jQuery object for the DOM node
-   * @final
-   * @public
-   */
-  $(selector) {
-    const $element = $(this.element);
-
-    return selector ? $element.find(selector) : $element;
-  }
-
-  /**
-   * Called after the component's root element is redrawn. This hook can be used
-   * to perform any actions on the DOM, both on the initial draw and any
-   * subsequent redraws. See Mithril's documentation for more information.
-   *
-   * @see https://lhorie.github.io/mithril/mithril.html#the-config-attribute
-   * @param {Boolean} isInitialized
-   * @param {Object} context
-   * @param {Object} vdom
-   * @public
-   */
-  config() {}
-
-  /**
-   * Get the virtual DOM that represents the component's view.
-   *
-   * @return {Object} The virtual DOM
-   * @protected
-   */
-  view() {
-    throw new Error('Component#view must be implemented by subclass');
-  }
-
-  /**
-   * Get a Mithril component object for this component, preloaded with props.
-   *
-   * @see https://lhorie.github.io/mithril/mithril.component.html
-   * @param {Object} [props] Properties to set on the component
-   * @param children
-   * @return {Object} The Mithril component object
-   * @property {function} controller
-   * @property {function} view
-   * @property {Object} component The class of this component
-   * @property {Object} props The props that were passed to the component
-   * @public
-   */
-  static component(props = {}, children = null) {
-    const componentProps = Object.assign({}, props);
-
-    if (children) componentProps.children = children;
-
-    this.initProps(componentProps);
-
-    // Set up a function for Mithril to get the component's view. It will accept
-    // the component's controller (which happens to be the component itself, in
-    // our case), update its props with the ones supplied, and then render the view.
-    const view = (component) => {
-      component.props = componentProps;
-      return component.render();
-    };
-
-    // Mithril uses this property on the view function to cache component
-    // controllers between redraws, thus persisting component state.
-    view.$original = this.prototype.view;
-
-    // Our output object consists of a controller constructor + a view function
-    // which Mithril will use to instantiate and render the component. We also
-    // attach a reference to the props that were passed through and the
-    // component's class for reference.
-    const output = {
-      controller: this.bind(undefined, componentProps),
-      view: view,
-      props: componentProps,
-      component: this,
-    };
-
-    // If a `key` prop was set, then we'll assume that we want that to actually
-    // show up as an attribute on the component object so that Mithril's key
-    // algorithm can be applied.
-    if (componentProps.key) {
-      output.attrs = { key: componentProps.key };
-    }
-
-    return output;
-  }
-
-  /**
-   * Initialize the component's props.
-   *
-   * @param {Object} props
-   * @public
-   */
-  static initProps(props) {}
-}

js/src/common/Component.ts

@@ -0,0 +1,168 @@
+import * as Mithril from 'mithril';
+
+let deprecatedPropsWarned = false;
+let deprecatedInitPropsWarned = false;
+
+export interface ComponentAttrs extends Mithril.Attributes {}
+
+/**
+ * The `Component` class defines a user interface 'building block'. A component
+ * generates a virtual DOM to be rendered on each redraw.
+ *
+ * Essentially, this is a wrapper for Mithril's components that adds several useful features:
+ *
+ *  - In the `oninit` and `onbeforeupdate` lifecycle hooks, we store vnode attrs in `this.attrs.
+ *    This allows us to use attrs across components without having to pass the vnode to every single
+ *    method.
+ *  - The static `initAttrs` method allows a convenient way to provide defaults (or to otherwise modify)
+ *    the attrs that have been passed into a component.
+ *  - When the component is created in the DOM, we store its DOM element under `this.element`; this lets
+ *    us use jQuery to modify child DOM state from internal methods via the `this.$()` method.
+ *  - A convenience `component` method, which serves as an alternative to hyperscript and JSX.
+ *
+ * As with other Mithril components, components extending Component can be initialized
+ * and nested using JSX, hyperscript, or a combination of both. The `component` method can also
+ * be used.
+ *
+ * @example
+ * return m('div', <MyComponent foo="bar"><p>Hello World</p></MyComponent>);
+ *
+ * @example
+ * return m('div', MyComponent.component({foo: 'bar'), m('p', 'Hello World!'));
+ *
+ * @see https://mithril.js.org/components.html
+ */
+export default abstract class Component<T extends ComponentAttrs = ComponentAttrs> implements Mithril.ClassComponent<T> {
+  /**
+   * The root DOM element for the component.
+   */
+  protected element!: Element;
+
+  /**
+   * The attributes passed into the component.
+   *
+   * @see https://mithril.js.org/components.html#passing-data-to-components
+   */
+  protected attrs!: T;
+
+  /**
+   * @inheritdoc
+   */
+  abstract view(vnode: Mithril.Vnode<T, this>): Mithril.Children;
+
+  /**
+   * @inheritdoc
+   */
+  oninit(vnode: Mithril.Vnode<T, this>) {
+    this.setAttrs(vnode.attrs);
+  }
+
+  /**
+   * @inheritdoc
+   */
+  oncreate(vnode: Mithril.VnodeDOM<T, this>) {
+    this.element = vnode.dom;
+  }
+
+  /**
+   * @inheritdoc
+   */
+  onbeforeupdate(vnode: Mithril.VnodeDOM<T, this>) {
+    this.setAttrs(vnode.attrs);
+  }
+
+  /**
+   * Returns a jQuery object for this component's element. If you pass in a
+   * selector string, this method will return a jQuery object, using the current
+   * element as its buffer.
+   *
+   * For example, calling `component.$('li')` will return a jQuery object
+   * containing all of the `li` elements inside the DOM element of this
+   * component.
+   *
+   * @param {String} [selector] a jQuery-compatible selector string
+   * @returns {jQuery} the jQuery object for the DOM node
+   * @final
+   */
+  protected $(selector) {
+    const $element = $(this.element);
+
+    return selector ? $element.find(selector) : $element;
+  }
+
+  /**
+   * Convenience method to attach a component without JSX.
+   * Has the same effect as calling `m(THIS_CLASS, attrs, children)`.
+   *
+   * @see https://mithril.js.org/hyperscript.html#mselector,-attributes,-children
+   */
+  static component(attrs = {}, children = null): Mithril.Vnode {
+    const componentAttrs = Object.assign({}, attrs);
+
+    return m(this as any, componentAttrs, children);
+  }
+
+  /**
+   * Saves a reference to the vnode attrs after running them through initAttrs,
+   * and checking for common issues.
+   */
+  private setAttrs(attrs: T = {} as T): void {
+    (this.constructor as typeof Component).initAttrs(attrs);
+
+    if (attrs) {
+      if ('children' in attrs) {
+        throw new Error(
+          `[${
+            (this.constructor as any).name
+          }] The "children" attribute of attrs should never be used. Either pass children in as the vnode children or rename the attribute`
+        );
+      }
+
+      if ('tag' in attrs) {
+        throw new Error(`[${(this.constructor as any).name}] You cannot use the "tag" attribute name with Mithril 2.`);
+      }
+    }
+
+    this.attrs = attrs;
+  }
+
+  /**
+   * Initialize the component's attrs.
+   *
+   * This can be used to assign default values for missing, optional attrs.
+   */
+  protected static initAttrs<T>(attrs: T): void {
+    // Deprecated, part of Mithril 2 BC layer
+    if ('initProps' in this && !deprecatedInitPropsWarned) {
+      deprecatedInitPropsWarned = true;
+      console.warn('initProps is deprecated, please use initAttrs instead.');
+      (this as any).initProps(attrs);
+    }
+  }
+
+  // BEGIN DEPRECATED MITHRIL 2 BC LAYER
+
+  /**
+   * The attributes passed into the component.
+   *
+   * @see https://mithril.js.org/components.html#passing-data-to-components
+   *
+   * @deprecated, use attrs instead.
+   */
+  get props() {
+    if (!deprecatedPropsWarned) {
+      deprecatedPropsWarned = true;
+      console.warn('this.props is deprecated, please use this.attrs instead.');
+    }
+    return this.attrs;
+  }
+  set props(props) {
+    if (!deprecatedPropsWarned) {
+      deprecatedPropsWarned = true;
+      console.warn('this.props is deprecated, please use this.attrs instead.');
+    }
+    this.attrs = props;
+  }
+
+  // END DEPRECATED MITHRIL 2 BC LAYER
+}

js/src/common/Fragment.ts

@@ -0,0 +1,74 @@
+import * as Mithril from 'mithril';
+
+/**
+ * The `Fragment` class represents a chunk of DOM that is rendered once with Mithril and then takes
+ * over control of its own DOM and lifecycle.
+ *
+ * This is very similar to the `Component` wrapper class, but is used for more fine-grained control over
+ * the rendering and display of some significant chunks of the DOM. In contrast to components, fragments
+ * do not offer Mithril's lifecycle hooks.
+ *
+ * Use this when you want to enjoy the benefits of JSX / VDOM for initial rendering, combined with
+ * small helper methods that then make updates to that DOM directly, instead of fully redrawing
+ * everything through Mithril.
+ *
+ * This should only be used when necessary, and only with `m.render`. If you are unsure whether you need
+ * this or `Component, you probably need `Component`.
+ */
+export default abstract class Fragment {
+  /**
+   * The root DOM element for the fragment.
+   */
+  protected element!: Element;
+
+  /**
+   * Returns a jQuery object for this fragment's element. If you pass in a
+   * selector string, this method will return a jQuery object, using the current
+   * element as its buffer.
+   *
+   * For example, calling `fragment.$('li')` will return a jQuery object
+   * containing all of the `li` elements inside the DOM element of this
+   * fragment.
+   *
+   * @param {String} [selector] a jQuery-compatible selector string
+   * @returns {jQuery} the jQuery object for the DOM node
+   * @final
+   */
+  public $(selector) {
+    const $element = $(this.element);
+
+    return selector ? $element.find(selector) : $element;
+  }
+
+  /**
+   * Get the renderable virtual DOM that represents the fragment's view.
+   *
+   * This should NOT be overridden by subclasses. Subclasses wishing to define
+   * their virtual DOM should override Fragment#view instead.
+   *
+   * @example
+   * const fragment = new MyFragment();
+   * m.render(document.body, fragment.render());
+   *
+   * @final
+   */
+  public render(): Mithril.Vnode<Mithril.Attributes, this> {
+    const vdom = this.view();
+
+    vdom.attrs = vdom.attrs || {};
+
+    const originalOnCreate = vdom.attrs.oncreate;
+
+    vdom.attrs.oncreate = (vnode) => {
+      this.element = vnode.dom;
+      if (originalOnCreate) originalOnCreate.apply(this, [vnode]);
+    };
+
+    return vdom;
+  }
+
+  /**
+   * Creates a view out of virtual elements.
+   */
+  abstract view(): Mithril.Vnode<Mithril.Attributes, this>;
+}

js/src/common/Model.js

@@ -161,7 +161,7 @@ export default class Model {
           {
             method: this.exists ? 'PATCH' : 'POST',
             url: app.forum.attribute('apiUrl') + this.apiEndpoint(),
-            data: request,
+            body: request,
           },
           options
         )
@@ -180,7 +180,7 @@ export default class Model {
         // old data! We'll revert to that and let others handle the error.
         (response) => {
           this.pushData(oldData);
-          m.lazyRedraw();
+          m.redraw();
           throw response;
         }
       );
@@ -189,13 +189,13 @@ export default class Model {
   /**
    * Send a request to delete the resource.
    *
-   * @param {Object} data Data to send along with the DELETE request.
+   * @param {Object} body Data to send along with the DELETE request.
    * @param {Object} [options]
    * @return {Promise}
    * @public
    */
-  delete(data, options = {}) {
-    if (!this.exists) return m.deferred().resolve().promise;
+  delete(body, options = {}) {
+    if (!this.exists) return Promise.resolve();
 
     return app
       .request(
@@ -203,7 +203,7 @@ export default class Model {
           {
             method: 'DELETE',
             url: app.forum.attribute('apiUrl') + this.apiEndpoint(),
-            data,
+            body,
           },
           options
         )

js/src/common/Session.js

@@ -30,13 +30,13 @@ export default class Session {
    * @return {Promise}
    * @public
    */
-  login(data, options = {}) {
+  login(body, options = {}) {
     return app.request(
       Object.assign(
         {
           method: 'POST',
-          url: app.forum.attribute('baseUrl') + '/login',
-          data,
+          url: `${app.forum.attribute('baseUrl')}/login`,
+          body,
         },
         options
       )
@@ -49,6 +49,6 @@ export default class Session {
    * @public
    */
   logout() {
-    window.location = app.forum.attribute('baseUrl') + '/logout?token=' + this.csrfToken;
+    window.location = `${app.forum.attribute('baseUrl')}/logout?token=${this.csrfToken}`;
   }
 }

js/src/common/Store.js

@@ -82,13 +82,13 @@ export default class Store {
    * @public
    */
   find(type, id, query = {}, options = {}) {
-    let data = query;
+    let params = query;
     let url = app.forum.attribute('apiUrl') + '/' + type;
 
     if (id instanceof Array) {
       url += '?filter[id]=' + id.join(',');
     } else if (typeof id === 'object') {
-      data = id;
+      params = id;
     } else if (id) {
       url += '/' + id;
     }
@@ -99,7 +99,7 @@ export default class Store {
           {
             method: 'GET',
             url,
-            data,
+            params,
           },
           options
         )

js/src/common/Translator.js

@@ -1,4 +1,3 @@
-import User from './models/User';
 import username from './helpers/username';
 import extract from './utils/extract';
 
@@ -71,18 +70,34 @@ export default class Translator {
       const match = part.match(new RegExp('{([a-z0-9_]+)}|<(/?)([a-z0-9_]+)>', 'i'));
 
       if (match) {
+        // Either an opening or closing tag.
         if (match[1]) {
           open[0].push(input[match[1]]);
         } else if (match[3]) {
           if (match[2]) {
+            // Closing tag. We start by removing all raw children (generally in the form of strings) from the temporary
+            // holding array, then run them through m.fragment to convert them to vnodes. Usually this will just give us a
+            // text vnode, but using m.fragment as opposed to an explicit conversion should be more flexible. This is necessary because
+            // otherwise, our generated vnode will have raw strings as its children, and mithril expects vnodes.
+            // Finally, we add the now-processed vnodes back onto the holding array (which is the same object in memory as the
+            // children array of the vnode we are currently processing), and remove the reference to the holding array so that
+            // further text will be added to the full set of returned elements.
+            const rawChildren = open[0].splice(0, open[0].length);
+            open[0].push(...m.fragment(rawChildren).children);
             open.shift();
           } else {
+            // If a vnode with a matching tag was provided in the translator input, we use that. Otherwise, we create a new vnode
+            // with this tag, and an empty children array (since we're expecting to insert children, as that's the point of having this in translator)
             let tag = input[match[3]] || { tag: match[3], children: [] };
             open[0].push(tag);
+            // Insert the tag's children array as the first element of open, so that text in between the opening
+            // and closing tags will be added to the tag's children, not to the full set of returned elements.
             open.unshift(tag.children || tag);
           }
         }
       } else {
+        // Not an html tag, we add it to open[0], which is either the full set of returned elements (vnodes and text),
+        // or if an html tag is currently being processed, the children attribute of that html tag's vnode.
         open[0].push(part);
       }
     });

js/src/common/compat.js

@@ -12,15 +12,20 @@ import anchorScroll from './utils/anchorScroll';
 import RequestError from './utils/RequestError';
 import abbreviateNumber from './utils/abbreviateNumber';
 import * as string from './utils/string';
+import Stream from './utils/Stream';
 import SubtreeRetainer from './utils/SubtreeRetainer';
+import setRouteWithForcedRefresh from './utils/setRouteWithForcedRefresh';
 import extract from './utils/extract';
 import ScrollListener from './utils/ScrollListener';
 import stringToColor from './utils/stringToColor';
+import subclassOf from './utils/subclassOf';
+import SuperTextarea from './utils/SuperTextarea';
 import patchMithril from './utils/patchMithril';
 import classList from './utils/classList';
 import extractText from './utils/extractText';
 import formatNumber from './utils/formatNumber';
 import mapRoutes from './utils/mapRoutes';
+import withAttr from './utils/withAttr';
 import Notification from './models/Notification';
 import User from './models/User';
 import Post from './models/Post';
@@ -43,6 +48,7 @@ import FieldSet from './components/FieldSet';
 import Select from './components/Select';
 import Navigation from './components/Navigation';
 import Alert from './components/Alert';
+import Link from './components/Link';
 import LinkButton from './components/LinkButton';
 import Checkbox from './components/Checkbox';
 import SelectDropdown from './components/SelectDropdown';
@@ -61,6 +67,8 @@ import highlight from './helpers/highlight';
 import username from './helpers/username';
 import userOnline from './helpers/userOnline';
 import listItems from './helpers/listItems';
+import Fragment from './Fragment';
+import DefaultResolver from './resolvers/DefaultResolver';
 
 export default {
   extend: extend,
@@ -81,11 +89,16 @@ export default {
   'utils/extract': extract,
   'utils/ScrollListener': ScrollListener,
   'utils/stringToColor': stringToColor,
+  'utils/Stream': Stream,
+  'utils/subclassOf': subclassOf,
+  'utils/SuperTextarea': SuperTextarea,
+  'utils/setRouteWithForcedRefresh': setRouteWithForcedRefresh,
   'utils/patchMithril': patchMithril,
   'utils/classList': classList,
   'utils/extractText': extractText,
   'utils/formatNumber': formatNumber,
   'utils/mapRoutes': mapRoutes,
+  'utils/withAttr': withAttr,
   'models/Notification': Notification,
   'models/User': User,
   'models/Post': Post,
@@ -93,6 +106,7 @@ export default {
   'models/Group': Group,
   'models/Forum': Forum,
   Component: Component,
+  Fragment: Fragment,
   Translator: Translator,
   'components/AlertManager': AlertManager,
   'components/Page': Page,
@@ -108,6 +122,7 @@ export default {
   'components/Select': Select,
   'components/Navigation': Navigation,
   'components/Alert': Alert,
+  'components/Link': Link,
   'components/LinkButton': LinkButton,
   'components/Checkbox': Checkbox,
   'components/SelectDropdown': SelectDropdown,
@@ -126,4 +141,5 @@ export default {
   'helpers/username': username,
   'helpers/userOnline': userOnline,
   'helpers/listItems': listItems,
+  'resolvers/DefaultResolver': DefaultResolver,
 };

js/src/common/components/Alert.tsx

@@ -1,31 +1,33 @@
-import Component from '../Component';
+import Component, { ComponentAttrs } from '../Component';
 import Button from './Button';
 import listItems from '../helpers/listItems';
 import extract from '../utils/extract';
+import Mithril from 'mithril';
+
+export interface AlertAttrs extends ComponentAttrs {
+  /** The type of alert this is. Will be used to give the alert a class name of `Alert--{type}`. */
+  type?: string;
+  /** An array of controls to show in the alert. */
+  controls?: Mithril.Children;
+  /** Whether or not the alert can be dismissed. */
+  dismissible?: boolean;
+  /** A callback to run when the alert is dismissed */
+  ondismiss?: Function;
+}
 
 /**
  * The `Alert` component represents an alert box, which contains a message,
  * some controls, and may be dismissible.
- *
- * The alert may have the following special props:
- *
- * - `type` The type of alert this is. Will be used to give the alert a class
- *   name of `Alert--{type}`.
- * - `controls` An array of controls to show in the alert.
- * - `dismissible` Whether or not the alert can be dismissed.
- * - `ondismiss` A callback to run when the alert is dismissed.
- *
- * All other props will be assigned as attributes on the alert element.
  */
-export default class Alert extends Component {
-  view() {
-    const attrs = Object.assign({}, this.props);
+export default class Alert<T extends AlertAttrs = AlertAttrs> extends Component<T> {
+  view(vnode: Mithril.Vnode) {
+    const attrs = Object.assign({}, this.attrs);
 
     const type = extract(attrs, 'type');
     attrs.className = 'Alert Alert--' + type + ' ' + (attrs.className || '');
 
-    const children = extract(attrs, 'children');
-    const controls = extract(attrs, 'controls') || [];
+    const content = extract(attrs, 'content') || vnode.children;
+    const controls = (extract(attrs, 'controls') || []) as Mithril.ChildArray;
 
     // If the alert is meant to be dismissible (which is the case by default),
     // then we will create a dismiss button to append as the final control in
@@ -40,7 +42,7 @@ export default class Alert extends Component {
 
     return (
       <div {...attrs}>
-        <span className="Alert-body">{children}</span>
+        <span className="Alert-body">{content}</span>
         <ul className="Alert-controls">{listItems(controls.concat(dismissControl))}</ul>
       </div>
     );

js/src/common/components/AlertManager.js

@@ -6,8 +6,10 @@ import Alert from './Alert';
  * be shown and dismissed.
  */
 export default class AlertManager extends Component {
-  init() {
-    this.state = this.props.state;
+  oninit(vnode) {
+    super.oninit(vnode);
+
+    this.state = this.attrs.state;
   }
 
   view() {
@@ -15,17 +17,12 @@ export default class AlertManager extends Component {
       <div className="AlertManager">
         {Object.entries(this.state.getActiveAlerts()).map(([key, alert]) => (
           <div className="AlertManager-alert">
-            {(alert.componentClass || Alert).component({ ...alert.attrs, ondismiss: this.state.dismiss.bind(this.state, key) })}
+            <alert.componentClass {...alert.attrs} ondismiss={this.state.dismiss.bind(this.state, key)}>
+              {alert.children}
+            </alert.componentClass>
           </div>
         ))}
       </div>
     );
   }
-
-  config(isInitialized, context) {
-    // Since this component is 'above' the content of the page (that is, it is a
-    // part of the global UI that persists between routes), we will flag the DOM
-    // to be retained across route changes.
-    context.retain = true;
-  }
 }

js/src/common/components/Badge.js

@@ -6,18 +6,18 @@ import extract from '../utils/extract';
  * The `Badge` component represents a user/discussion badge, indicating some
  * status (e.g. a discussion is stickied, a user is an admin).
  *
- * A badge may have the following special props:
+ * A badge may have the following special attrs:
  *
  * - `type` The type of badge this is. This will be used to give the badge a
  *   class name of `Badge--{type}`.
  * - `icon` The name of an icon to show inside the badge.
  * - `label`
  *
- * All other props will be assigned as attributes on the badge element.
+ * All other attrs will be assigned as attributes on the badge element.
  */
 export default class Badge extends Component {
   view() {
-    const attrs = Object.assign({}, this.props);
+    const attrs = Object.assign({}, this.attrs);
     const type = extract(attrs, 'type');
     const iconName = extract(attrs, 'icon');
 
@@ -27,9 +27,9 @@ export default class Badge extends Component {
     return <span {...attrs}>{iconName ? icon(iconName, { className: 'Badge-icon' }) : m.trust('&nbsp;')}</span>;
   }
 
-  config(isInitialized) {
-    if (isInitialized) return;
+  oncreate(vnode) {
+    super.oncreate(vnode);
 
-    if (this.props.label) this.$().tooltip();
+    if (this.attrs.label) this.$().tooltip();
   }
 }

js/src/common/components/Button.js

@@ -1,12 +1,15 @@
 import Component from '../Component';
 import icon from '../helpers/icon';
+import classList from '../utils/classList';
 import extract from '../utils/extract';
 import extractText from '../utils/extractText';
 import LoadingIndicator from './LoadingIndicator';
 
 /**
  * The `Button` component defines an element which, when clicked, performs an
- * action. The button may have the following special props:
+ * action.
+ *
+ * ### Attrs
  *
  * - `icon` The name of the icon class. If specified, the button will be given a
  *   'has-icon' class name.
@@ -15,41 +18,38 @@ import LoadingIndicator from './LoadingIndicator';
  *   removed.
  * - `loading` Whether or not the button should be in a disabled loading state.
  *
- * All other props will be assigned as attributes on the button element.
+ * All other attrs will be assigned as attributes on the button element.
  *
  * Note that a Button has no default class names. This is because a Button can
  * be used to represent any generic clickable control, like a menu item.
  */
 export default class Button extends Component {
-  view() {
-    const attrs = Object.assign({}, this.props);
+  view(vnode) {
+    const attrs = Object.assign({}, this.attrs);
 
-    delete attrs.children;
-
-    attrs.className = attrs.className || '';
     attrs.type = attrs.type || 'button';
 
     // If a tooltip was provided for buttons without additional content, we also
     // use this tooltip as text for screen readers
-    if (attrs.title && !this.props.children) {
+    if (attrs.title && !vnode.children) {
       attrs['aria-label'] = attrs.title;
     }
 
     // If nothing else is provided, we use the textual button content as tooltip
-    if (!attrs.title && this.props.children) {
-      attrs.title = extractText(this.props.children);
+    if (!attrs.title && vnode.children) {
+      attrs.title = extractText(vnode.children);
     }
 
     const iconName = extract(attrs, 'icon');
-    if (iconName) attrs.className += ' hasIcon';
 
     const loading = extract(attrs, 'loading');
     if (attrs.disabled || loading) {
-      attrs.className += ' disabled' + (loading ? ' loading' : '');
       delete attrs.onclick;
     }
 
-    return <button {...attrs}>{this.getButtonContent()}</button>;
+    attrs.className = classList([attrs.className, iconName && 'hasIcon', (attrs.disabled || loading) && 'disabled', loading && 'loading']);
+
+    return <button {...attrs}>{this.getButtonContent(vnode.children)}</button>;
   }
 
   /**
@@ -58,13 +58,13 @@ export default class Button extends Component {
    * @return {*}
    * @protected
    */
-  getButtonContent() {
-    const iconName = this.props.icon;
+  getButtonContent(children) {
+    const iconName = this.attrs.icon;
 
     return [
       iconName && iconName !== true ? icon(iconName, { className: 'Button-icon' }) : '',
-      this.props.children ? <span className="Button-label">{this.props.children}</span> : '',
-      this.props.loading ? LoadingIndicator.component({ size: 'tiny', className: 'LoadingIndicator--inline' }) : '',
+      children ? <span className="Button-label">{children}</span> : '',
+      this.attrs.loading ? <LoadingIndicator size="tiny" className="LoadingIndicator--inline" /> : '',
     ];
   }
 }

js/src/common/components/Checkbox.js

@@ -1,11 +1,13 @@
 import Component from '../Component';
 import LoadingIndicator from './LoadingIndicator';
 import icon from '../helpers/icon';
+import classList from '../utils/classList';
+import withAttr from '../utils/withAttr';
 
 /**
  * The `Checkbox` component defines a checkbox input.
  *
- * ### Props
+ * ### Attrs
  *
  * - `state` Whether or not the checkbox is checked.
  * - `className` The class name for the root element.
@@ -15,19 +17,24 @@ import icon from '../helpers/icon';
  * - `children` A text label to display next to the checkbox.
  */
 export default class Checkbox extends Component {
-  view() {
+  view(vnode) {
     // Sometimes, false is stored in the DB as '0'. This is a temporary
     // conversion layer until a more robust settings encoding is introduced
-    if (this.props.state === '0') this.props.state = false;
-    let className = 'Checkbox ' + (this.props.state ? 'on' : 'off') + ' ' + (this.props.className || '');
-    if (this.props.loading) className += ' loading';
-    if (this.props.disabled) className += ' disabled';
+    if (this.attrs.state === '0') this.attrs.state = false;
+
+    const className = classList([
+      'Checkbox',
+      this.attrs.state ? 'on' : 'off',
+      this.attrs.className,
+      this.attrs.loading && 'loading',
+      this.attrs.disabled && 'disabled',
+    ]);
 
     return (
       <label className={className}>
-        <input type="checkbox" checked={this.props.state} disabled={this.props.disabled} onchange={m.withAttr('checked', this.onchange.bind(this))} />
+        <input type="checkbox" checked={this.attrs.state} disabled={this.attrs.disabled} onchange={withAttr('checked', this.onchange.bind(this))} />
         <div className="Checkbox-display">{this.getDisplay()}</div>
-        {this.props.children}
+        {vnode.children}
       </label>
     );
   }
@@ -39,7 +46,7 @@ export default class Checkbox extends Component {
    * @protected
    */
   getDisplay() {
-    return this.props.loading ? LoadingIndicator.component({ size: 'tiny' }) : icon(this.props.state ? 'fas fa-check' : 'fas fa-times');
+    return this.attrs.loading ? <LoadingIndicator size="tiny" /> : icon(this.attrs.state ? 'fas fa-check' : 'fas fa-times');
   }
 
   /**
@@ -49,6 +56,6 @@ export default class Checkbox extends Component {
    * @protected
    */
   onchange(checked) {
-    if (this.props.onchange) this.props.onchange(checked, this);
+    if (this.attrs.onchange) this.attrs.onchange(checked, this);
   }
 }

js/src/common/components/ConfirmDocumentUnload.js

@@ -5,7 +5,7 @@ import Component from '../Component';
  * event handler that prevents closing the browser window/tab based on the
  * return value of a given callback prop.
  *
- * ### Props
+ * ### Attrs
  *
  * - `when` - a callback returning true when the browser should prompt for
  *            confirmation before closing the window/tab
@@ -17,21 +17,24 @@ import Component from '../Component';
  *
  */
 export default class ConfirmDocumentUnload extends Component {
-  config(isInitialized, context) {
-    if (isInitialized) return;
-
-    const handler = () => this.props.when() || undefined;
-
-    $(window).on('beforeunload', handler);
-
-    context.onunload = () => {
-      $(window).off('beforeunload', handler);
-    };
+  handler() {
+    return this.attrs.when() || undefined;
   }
 
-  view() {
+  oncreate(vnode) {
+    super.oncreate(vnode);
+
+    this.boundHandler = this.handler.bind(this);
+    $(window).on('beforeunload', this.boundHandler);
+  }
+
+  onremove() {
+    $(window).off('beforeunload', this.boundHandler);
+  }
+
+  view(vnode) {
     // To avoid having to render another wrapping <div> here, we assume that
     // this component is only wrapped around a single element / component.
-    return this.props.children[0];
+    return vnode.children[0];
   }
 }

js/src/common/components/Dropdown.js

@@ -6,7 +6,7 @@ import listItems from '../helpers/listItems';
  * The `Dropdown` component displays a button which, when clicked, shows a
  * dropdown menu beneath it.
  *
- * ### Props
+ * ### Attrs
  *
  * - `buttonClassName` A class name to apply to the dropdown toggle button.
  * - `menuClassName` A class name to apply to the dropdown menu.
@@ -19,33 +19,33 @@ import listItems from '../helpers/listItems';
  * The children will be displayed as a list inside of the dropdown menu.
  */
 export default class Dropdown extends Component {
-  static initProps(props) {
-    super.initProps(props);
-
-    props.className = props.className || '';
-    props.buttonClassName = props.buttonClassName || '';
-    props.menuClassName = props.menuClassName || '';
-    props.label = props.label || '';
-    props.caretIcon = typeof props.caretIcon !== 'undefined' ? props.caretIcon : 'fas fa-caret-down';
+  static initAttrs(attrs) {
+    attrs.className = attrs.className || '';
+    attrs.buttonClassName = attrs.buttonClassName || '';
+    attrs.menuClassName = attrs.menuClassName || '';
+    attrs.label = attrs.label || '';
+    attrs.caretIcon = typeof attrs.caretIcon !== 'undefined' ? attrs.caretIcon : 'fas fa-caret-down';
   }
 
-  init() {
+  oninit(vnode) {
+    super.oninit(vnode);
+
     this.showing = false;
   }
 
-  view() {
-    const items = this.props.children ? listItems(this.props.children) : [];
+  view(vnode) {
+    const items = vnode.children ? listItems(vnode.children) : [];
 
     return (
-      <div className={'ButtonGroup Dropdown dropdown ' + this.props.className + ' itemCount' + items.length + (this.showing ? ' open' : '')}>
-        {this.getButton()}
+      <div className={'ButtonGroup Dropdown dropdown ' + this.attrs.className + ' itemCount' + items.length + (this.showing ? ' open' : '')}>
+        {this.getButton(vnode.children)}
         {this.getMenu(items)}
       </div>
     );
   }
 
-  config(isInitialized) {
-    if (isInitialized) return;
+  oncreate(vnode) {
+    super.oncreate(vnode);
 
     // When opening the dropdown menu, work out if the menu goes beyond the
     // bottom of the viewport. If it does, we will apply class to make it show
@@ -53,8 +53,8 @@ export default class Dropdown extends Component {
     this.$().on('shown.bs.dropdown', () => {
       this.showing = true;
 
-      if (this.props.onshow) {
-        this.props.onshow();
+      if (this.attrs.onshow) {
+        this.attrs.onshow();
       }
 
       m.redraw();
@@ -76,8 +76,8 @@ export default class Dropdown extends Component {
     this.$().on('hidden.bs.dropdown', () => {
       this.showing = false;
 
-      if (this.props.onhide) {
-        this.props.onhide();
+      if (this.attrs.onhide) {
+        this.attrs.onhide();
       }
 
       m.redraw();
@@ -90,10 +90,10 @@ export default class Dropdown extends Component {
    * @return {*}
    * @protected
    */
-  getButton() {
+  getButton(children) {
     return (
-      <button className={'Dropdown-toggle ' + this.props.buttonClassName} data-toggle="dropdown" onclick={this.props.onclick}>
-        {this.getButtonContent()}
+      <button className={'Dropdown-toggle ' + this.attrs.buttonClassName} data-toggle="dropdown" onclick={this.attrs.onclick}>
+        {this.getButtonContent(children)}
       </button>
     );
   }
@@ -104,15 +104,15 @@ export default class Dropdown extends Component {
    * @return {*}
    * @protected
    */
-  getButtonContent() {
+  getButtonContent(children) {
     return [
-      this.props.icon ? icon(this.props.icon, { className: 'Button-icon' }) : '',
-      <span className="Button-label">{this.props.label}</span>,
-      this.props.caretIcon ? icon(this.props.caretIcon, { className: 'Button-caret' }) : '',
+      this.attrs.icon ? icon(this.attrs.icon, { className: 'Button-icon' }) : '',
+      <span className="Button-label">{this.attrs.label}</span>,
+      this.attrs.caretIcon ? icon(this.attrs.caretIcon, { className: 'Button-caret' }) : '',
     ];
   }
 
   getMenu(items) {
-    return <ul className={'Dropdown-menu dropdown-menu ' + this.props.menuClassName}>{items}</ul>;
+    return <ul className={'Dropdown-menu dropdown-menu ' + this.attrs.menuClassName}>{items}</ul>;
   }
 }

js/src/common/components/FieldSet.js

@@ -11,11 +11,11 @@ import listItems from '../helpers/listItems';
  * The children should be an array of items to show in the fieldset.
  */
 export default class FieldSet extends Component {
-  view() {
+  view(vnode) {
     return (
-      <fieldset className={this.props.className}>
-        <legend>{this.props.label}</legend>
-        <ul>{listItems(this.props.children)}</ul>
+      <fieldset className={this.attrs.className}>
+        <legend>{this.attrs.label}</legend>
+        <ul>{listItems(vnode.children)}</ul>
       </fieldset>
     );
   }

js/src/common/components/GroupBadge.js

@@ -1,16 +1,16 @@
 import Badge from './Badge';
 
 export default class GroupBadge extends Badge {
-  static initProps(props) {
-    super.initProps(props);
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
 
-    if (props.group) {
-      props.icon = props.group.icon();
-      props.style = { backgroundColor: props.group.color() };
-      props.label = typeof props.label === 'undefined' ? props.group.nameSingular() : props.label;
-      props.type = 'group--' + props.group.id();
+    if (attrs.group) {
+      attrs.icon = attrs.group.icon();
+      attrs.style = { backgroundColor: attrs.group.color() };
+      attrs.label = typeof attrs.label === 'undefined' ? attrs.group.nameSingular() : attrs.label;
+      attrs.type = 'group--' + attrs.group.id();
 
-      delete props.group;
+      delete attrs.group;
     }
   }
 }

js/src/common/components/Link.js

@@ -0,0 +1,47 @@
+import Component from '../Component';
+import extract from '../utils/extract';
+
+/**
+ * The link component enables both internal and external links.
+ * It will return a regular HTML link for any links to external sites,
+ * and it will use Mithril's m.route.Link for any internal links.
+ *
+ * Links will default to internal; the 'external' attr must be set to
+ * `true` for the link to be external.
+ */
+export default class Link extends Component {
+  view(vnode) {
+    let { options = {}, ...attrs } = vnode.attrs;
+
+    attrs.href = attrs.href || '';
+
+    // For some reason, m.route.Link does not like vnode.text, so if present, we
+    // need to convert it to text vnodes and store it in children.
+    const children = vnode.children || { tag: '#', children: vnode.text };
+
+    if (attrs.external) {
+      return <a {...attrs}>{children}</a>;
+    }
+
+    // If the href URL of the link is the same as the current page path
+    // we will not add a new entry to the browser history.
+    // This allows us to still refresh the Page component
+    // without adding endless history entries.
+    if (attrs.href === m.route.get()) {
+      if (!('replace' in options)) options.replace = true;
+    }
+
+    // Mithril 2 does not completely rerender the page if a route change leads to the same route
+    // (or the same component handling a different route).
+    // Here, the `force` parameter will use Mithril's key system to force a full rerender
+    // see https://mithril.js.org/route.html#key-parameter
+    if (extract(attrs, 'force')) {
+      if (!('state' in options)) options.state = {};
+      if (!('key' in options.state)) options.state.key = Date.now();
+    }
+
+    attrs.options = options;
+
+    return <m.route.Link {...attrs}>{children}</m.route.Link>;
+  }
+}

js/src/common/components/LinkButton.js

@@ -1,38 +1,43 @@
 import Button from './Button';
+import Link from './Link';
 
 /**
  * The `LinkButton` component defines a `Button` which links to a route.
  *
- * ### Props
+ * ### Attrs
  *
- * All of the props accepted by `Button`, plus:
+ * All of the attrs accepted by `Button`, plus:
  *
  * - `active` Whether or not the page that this button links to is currently
  *   active.
  * - `href` The URL to link to. If the current URL `m.route()` matches this,
  *   the `active` prop will automatically be set to true.
+ * - `force` Whether the page should be fully rerendered. Defaults to `true`.
  */
 export default class LinkButton extends Button {
-  static initProps(props) {
-    props.active = this.isActive(props);
-    props.config = props.config || m.route;
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
+
+    attrs.active = this.isActive(attrs);
+    if (attrs.force === undefined) attrs.force = true;
   }
 
-  view() {
-    const vdom = super.view();
+  view(vnode) {
+    const vdom = super.view(vnode);
 
-    vdom.tag = 'a';
+    vdom.tag = Link;
+    vdom.attrs.active = String(vdom.attrs.active);
 
     return vdom;
   }
 
   /**
-   * Determine whether a component with the given props is 'active'.
+   * Determine whether a component with the given attrs is 'active'.
    *
-   * @param {Object} props
+   * @param {Object} attrs
    * @return {Boolean}
    */
-  static isActive(props) {
-    return typeof props.active !== 'undefined' ? props.active : m.route() === props.href;
+  static isActive(attrs) {
+    return typeof attrs.active !== 'undefined' ? attrs.active : m.route.get() === attrs.href;
   }
 }

js/src/common/components/LoadingIndicator.js

@@ -2,16 +2,17 @@ import Component from '../Component';
 import { Spinner } from 'spin.js';
 
 /**
- * The `LoadingIndicator` component displays a loading spinner with spin.js. It
- * may have the following special props:
+ * The `LoadingIndicator` component displays a loading spinner with spin.js.
+ *
+ * ### Attrs
  *
  * - `size` The spin.js size preset to use. Defaults to 'small'.
  *
- * All other props will be assigned as attributes on the element.
+ * All other attrs will be assigned as attributes on the DOM element.
  */
 export default class LoadingIndicator extends Component {
   view() {
-    const attrs = Object.assign({}, this.props);
+    const attrs = Object.assign({}, this.attrs);
 
     attrs.className = 'LoadingIndicator ' + (attrs.className || '');
     delete attrs.size;
@@ -19,12 +20,12 @@ export default class LoadingIndicator extends Component {
     return <div {...attrs}>{m.trust('&nbsp;')}</div>;
   }
 
-  config(isInitialized) {
-    if (isInitialized) return;
+  oncreate(vnode) {
+    super.oncreate(vnode);
 
     const options = { zIndex: 'auto', color: this.$().css('color') };
 
-    switch (this.props.size) {
+    switch (this.attrs.size) {
       case 'large':
         Object.assign(options, { lines: 10, length: 8, width: 4, radius: 8 });
         break;

js/src/common/components/Modal.js

@@ -14,23 +14,30 @@ export default class Modal extends Component {
    */
   static isDismissible = true;
 
-  init() {
-    /**
-     * Attributes for an alert component to show below the header.
-     *
-     * @type {object}
-     */
-    this.alertAttrs = null;
+  /**
+   * Attributes for an alert component to show below the header.
+   *
+   * @type {object}
+   */
+  alertAttrs = null;
+
+  oncreate(vnode) {
+    super.oncreate(vnode);
+
+    this.attrs.animateShow(() => this.onready());
   }
 
-  config(isInitialized, context) {
-    if (isInitialized) return;
-
-    this.props.onshow(() => this.onready());
-
-    context.onunload = () => {
-      this.props.onhide();
-    };
+  onbeforeremove() {
+    // If the global modal state currently contains a modal,
+    // we've just opened up a new one, and accordingly,
+    // we don't need to show a hide animation.
+    if (!this.attrs.state.modal) {
+      this.attrs.animateHide();
+      // Here, we ensure that the animation has time to complete.
+      // See https://mithril.js.org/lifecycle-methods.html#onbeforeremove
+      // Bootstrap's Modal.TRANSITION_DURATION is 300 ms.
+      return new Promise((resolve) => setTimeout(resolve, 300));
+    }
   }
 
   view() {
@@ -105,13 +112,11 @@ export default class Modal extends Component {
     this.$('form').find('input, select, textarea').first().focus().select();
   }
 
-  onhide() {}
-
   /**
    * Hide the modal.
    */
   hide() {
-    this.props.onhide();
+    this.attrs.state.close();
   }
 
   /**

js/src/common/components/ModalManager.js

@@ -6,36 +6,42 @@ import Component from '../Component';
  * overwrite the previous one.
  */
 export default class ModalManager extends Component {
-  init() {
-    this.state = this.props.state;
-  }
-
   view() {
-    const modal = this.state.modal;
+    const modal = this.attrs.state.modal;
 
     return (
       <div className="ModalManager modal fade">
-        {modal ? modal.componentClass.component({ ...modal.attrs, onshow: this.animateShow.bind(this), onhide: this.animateHide.bind(this) }) : ''}
+        {modal
+          ? modal.componentClass.component({
+              ...modal.attrs,
+              animateShow: this.animateShow.bind(this),
+              animateHide: this.animateHide.bind(this),
+              state: this.attrs.state,
+            })
+          : ''}
       </div>
     );
   }
 
-  config(isInitialized, context) {
-    if (isInitialized) return;
-
-    // Since this component is 'above' the content of the page (that is, it is a
-    // part of the global UI that persists between routes), we will flag the DOM
-    // to be retained across route changes.
-    context.retain = true;
+  oncreate(vnode) {
+    super.oncreate(vnode);
 
     // Ensure the modal state is notified about a closed modal, even when the
     // DOM-based Bootstrap JavaScript code triggered the closing of the modal,
     // e.g. via ESC key or a click on the modal backdrop.
-    this.$().on('hidden.bs.modal', this.state.close.bind(this.state));
+    this.$().on('hidden.bs.modal', this.attrs.state.close.bind(this.attrs.state));
   }
 
   animateShow(readyCallback) {
-    const dismissible = !!this.state.modal.componentClass.isDismissible;
+    const dismissible = !!this.attrs.state.modal.componentClass.isDismissible;
+
+    // If we are opening this modal while another modal is already open,
+    // the shown event will not run, because the modal is already open.
+    // So, we need to manually trigger the readyCallback.
+    if (this.$().hasClass('in')) {
+      readyCallback();
+      return;
+    }
 
     this.$()
       .one('shown.bs.modal', readyCallback)

js/src/common/components/Navigation.js

@@ -11,7 +11,7 @@ import LinkButton from './LinkButton';
  * If the app has a pane, it will also include a 'pin' button which toggles the
  * pinned state of the pane.
  *
- * Accepts the following props:
+ * Accepts the following attrs:
  *
  * - `className` The name of a class to set on the root element.
  * - `drawer` Whether or not to show a button to toggle the app's drawer if
@@ -23,7 +23,7 @@ export default class Navigation extends Component {
 
     return (
       <div
-        className={'Navigation ButtonGroup ' + (this.props.className || '')}
+        className={'Navigation ButtonGroup ' + (this.attrs.className || '')}
         onmouseenter={pane && pane.show.bind(pane)}
         onmouseleave={pane && pane.onmouseleave.bind(pane)}
       >
@@ -32,13 +32,6 @@ export default class Navigation extends Component {
     );
   }
 
-  config(isInitialized, context) {
-    // Since this component is 'above' the content of the page (that is, it is a
-    // part of the global UI that persists between routes), we will flag the DOM
-    // to be retained across route changes.
-    context.retain = true;
-  }
-
   /**
    * Get the back button.
    *
@@ -54,7 +47,6 @@ export default class Navigation extends Component {
       href: history.backUrl(),
       icon: 'fas fa-chevron-left',
       title: previous.title,
-      config: () => {},
       onclick: (e) => {
         if (e.shiftKey || e.ctrlKey || e.metaKey || e.which === 2) return;
         e.preventDefault();
@@ -88,7 +80,7 @@ export default class Navigation extends Component {
    * @protected
    */
   getDrawerButton() {
-    if (!this.props.drawer) return '';
+    if (!this.attrs.drawer) return '';
 
     const { drawer } = app;
     const user = app.session.user;

js/src/common/components/Page.js

@@ -7,9 +7,11 @@ import PageState from '../states/PageState';
  * @abstract
  */
 export default class Page extends Component {
-  init() {
+  oninit(vnode) {
+    super.oninit(vnode);
+
     app.previous = app.current;
-    app.current = new PageState(this.constructor);
+    app.current = new PageState(this.constructor, { routeName: this.attrs.routeName });
 
     app.drawer.hide();
     app.modal.close();
@@ -20,15 +22,30 @@ export default class Page extends Component {
      * @type {String}
      */
     this.bodyClass = '';
+
+    /**
+     * Whether we should scroll to the top of the page when its rendered.
+     *
+     * @type {Boolean}
+     */
+    this.scrollTopOnCreate = true;
   }
 
-  config(isInitialized, context) {
-    if (isInitialized) return;
+  oncreate(vnode) {
+    super.oncreate(vnode);
 
     if (this.bodyClass) {
       $('#app').addClass(this.bodyClass);
+    }
 
-      context.onunload = () => $('#app').removeClass(this.bodyClass);
+    if (this.scrollTopOnCreate) {
+      $(window).scrollTop(0);
+    }
+  }
+
+  onremove() {
+    if (this.bodyClass) {
+      $('#app').removeClass(this.bodyClass);
     }
   }
 }

js/src/common/components/Placeholder.js

@@ -4,7 +4,7 @@ import Component from '../Component';
  * The `Placeholder` component displays a muted text with some call to action,
  * usually used as an empty state.
  *
- * ### Props
+ * ### Attrs
  *
  * - `text`
  */
@@ -12,7 +12,7 @@ export default class Placeholder extends Component {
   view() {
     return (
       <div className="Placeholder">
-        <p>{this.props.text}</p>
+        <p>{this.attrs.text}</p>
       </div>
     );
   }

js/src/common/components/RequestErrorModal.js

@@ -6,11 +6,11 @@ export default class RequestErrorModal extends Modal {
   }
 
   title() {
-    return this.props.error.xhr ? `${this.props.error.xhr.status} ${this.props.error.xhr.statusText}` : '';
+    return this.attrs.error.xhr ? `${this.attrs.error.xhr.status} ${this.attrs.error.xhr.statusText}` : '';
   }
 
   content() {
-    const { error, formattedError } = this.props;
+    const { error, formattedError } = this.attrs;
 
     let responseText;
 
@@ -31,7 +31,7 @@ export default class RequestErrorModal extends Modal {
     return (
       <div className="Modal-body">
         <pre>
-          {this.props.error.options.method} {this.props.error.options.url}
+          {this.attrs.error.options.method} {this.attrs.error.options.url}
           <br />
           <br />
           {responseText}

js/src/common/components/Select.js

@@ -1,9 +1,10 @@
 import Component from '../Component';
 import icon from '../helpers/icon';
+import withAttr from '../utils/withAttr';
 
 /**
  * The `Select` component displays a <select> input, surrounded with some extra
- * elements for styling. It accepts the following props:
+ * elements for styling. It accepts the following attrs:
  *
  * - `options` A map of option values to labels.
  * - `onchange` A callback to run when the selected value is changed.
@@ -12,13 +13,13 @@ import icon from '../helpers/icon';
  */
 export default class Select extends Component {
   view() {
-    const { options, onchange, value, disabled } = this.props;
+    const { options, onchange, value, disabled } = this.attrs;
 
     return (
       <span className="Select">
         <select
           className="Select-input FormControl"
-          onchange={onchange ? m.withAttr('value', onchange.bind(this)) : undefined}
+          onchange={onchange ? withAttr('value', onchange.bind(this)) : undefined}
           value={value}
           disabled={disabled}
         >

js/src/common/components/SelectDropdown.js

@@ -1,31 +1,49 @@
 import Dropdown from './Dropdown';
 import icon from '../helpers/icon';
 
+/**
+ * Determines via a vnode is currently "active".
+ * Due to changes in Mithril 2, attrs will not be instantiated until AFTER view()
+ * is initially called on the parent component, so we can not always depend on the
+ * active attr to determine which element should be displayed as the "active child".
+ *
+ * This is a temporary patch, and as so, is not exported / placed in utils.
+ */
+function isActive(vnode) {
+  const tag = vnode.tag;
+
+  if ('initAttrs' in tag) {
+    tag.initAttrs(vnode.attrs);
+  }
+
+  return 'isActive' in tag ? tag.isActive(vnode.attrs) : vnode.attrs.active;
+}
+
 /**
  * The `SelectDropdown` component is the same as a `Dropdown`, except the toggle
  * button's label is set as the label of the first child which has a truthy
  * `active` prop.
  *
- * ### Props
+ * ### Attrs
  *
  * - `caretIcon`
  * - `defaultLabel`
  */
 export default class SelectDropdown extends Dropdown {
-  static initProps(props) {
-    props.caretIcon = typeof props.caretIcon !== 'undefined' ? props.caretIcon : 'fas fa-sort';
+  static initAttrs(attrs) {
+    attrs.caretIcon = typeof attrs.caretIcon !== 'undefined' ? attrs.caretIcon : 'fas fa-sort';
 
-    super.initProps(props);
+    super.initAttrs(attrs);
 
-    props.className += ' Dropdown--select';
+    attrs.className += ' Dropdown--select';
   }
 
-  getButtonContent() {
-    const activeChild = this.props.children.filter((child) => child.props.active)[0];
-    let label = (activeChild && activeChild.props.children) || this.props.defaultLabel;
+  getButtonContent(children) {
+    const activeChild = children.find(isActive);
+    let label = (activeChild && activeChild.children) || this.attrs.defaultLabel;
 
     if (label instanceof Array) label = label[0];
 
-    return [<span className="Button-label">{label}</span>, icon(this.props.caretIcon, { className: 'Button-caret' })];
+    return [<span className="Button-label">{label}</span>, icon(this.attrs.caretIcon, { className: 'Button-caret' })];
   }
 }

js/src/common/components/SplitDropdown.js

@@ -7,25 +7,25 @@ import icon from '../helpers/icon';
  * is displayed as its own button prior to the toggle button.
  */
 export default class SplitDropdown extends Dropdown {
-  static initProps(props) {
-    super.initProps(props);
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
 
-    props.className += ' Dropdown--split';
-    props.menuClassName += ' Dropdown-menu--right';
+    attrs.className += ' Dropdown--split';
+    attrs.menuClassName += ' Dropdown-menu--right';
   }
 
-  getButton() {
-    // Make a copy of the props of the first child component. We will assign
-    // these props to a new button, so that it has exactly the same behaviour as
+  getButton(children) {
+    // Make a copy of the attrs of the first child component. We will assign
+    // these attrs to a new button, so that it has exactly the same behaviour as
     // the first child.
-    const firstChild = this.getFirstChild();
-    const buttonProps = Object.assign({}, firstChild.props);
-    buttonProps.className = (buttonProps.className || '') + ' SplitDropdown-button Button ' + this.props.buttonClassName;
+    const firstChild = this.getFirstChild(children);
+    const buttonAttrs = Object.assign({}, firstChild.attrs);
+    buttonAttrs.className = (buttonAttrs.className || '') + ' SplitDropdown-button Button ' + this.attrs.buttonClassName;
 
     return [
-      Button.component(buttonProps),
-      <button className={'Dropdown-toggle Button Button--icon ' + this.props.buttonClassName} data-toggle="dropdown">
-        {icon(this.props.icon, { className: 'Button-icon' })}
+      Button.component(buttonAttrs, firstChild.children),
+      <button className={'Dropdown-toggle Button Button--icon ' + this.attrs.buttonClassName} data-toggle="dropdown">
+        {icon(this.attrs.icon, { className: 'Button-icon' })}
         {icon('fas fa-caret-down', { className: 'Button-caret' })}
       </button>,
     ];
@@ -38,8 +38,8 @@ export default class SplitDropdown extends Dropdown {
    * @return {*}
    * @protected
    */
-  getFirstChild() {
-    let firstChild = this.props.children;
+  getFirstChild(children) {
+    let firstChild = children;
 
     while (firstChild instanceof Array) firstChild = firstChild[0];
 

js/src/common/components/Switch.js

@@ -5,13 +5,13 @@ import Checkbox from './Checkbox';
  * a tick/cross one.
  */
 export default class Switch extends Checkbox {
-  static initProps(props) {
-    super.initProps(props);
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
 
-    props.className = (props.className || '') + ' Checkbox--switch';
+    attrs.className = (attrs.className || '') + ' Checkbox--switch';
   }
 
   getDisplay() {
-    return this.props.loading ? super.getDisplay() : '';
+    return this.attrs.loading ? super.getDisplay() : '';
   }
 }

js/src/common/helpers/avatar.js

@@ -25,7 +25,7 @@ export default function avatar(user, attrs = {}) {
     if (hasTitle) attrs.title = attrs.title || username;
 
     if (avatarUrl) {
-      return <img {...attrs} src={avatarUrl} />;
+      return <img {...attrs} src={avatarUrl} alt="" />;
     }
 
     content = username.charAt(0).toUpperCase();

js/src/common/helpers/fullTime.tsx

@@ -1,11 +1,11 @@
+import dayjs from 'dayjs';
+import * as Mithril from 'mithril';
+
 /**
  * The `fullTime` helper displays a formatted time string wrapped in a <time>
  * tag.
- *
- * @param {Date} time
- * @return {Object}
  */
-export default function fullTime(time) {
+export default function fullTime(time: Date): Mithril.Vnode {
   const d = dayjs(time);
 
   const datetime = d.format();

js/src/common/helpers/humanTime.tsx

@@ -1,14 +1,13 @@
+import dayjs from 'dayjs';
+import * as Mithril from 'mithril';
 import humanTimeUtil from '../utils/humanTime';
 
 /**
  * The `humanTime` helper displays a time in a human-friendly time-ago format
  * (e.g. '12 days ago'), wrapped in a <time> tag with other information about
  * the time.
- *
- * @param {Date} time
- * @return {Object}
  */
-export default function humanTime(time) {
+export default function humanTime(time: Date): Mithril.Vnode {
   const d = dayjs(time);
 
   const datetime = d.format();

js/src/common/helpers/icon.js

@@ -1,12 +0,0 @@
-/**
- * The `icon` helper displays an icon.
- *
- * @param {String} fontClass The full icon class, prefix and the icon’s name.
- * @param {Object} attrs Any other attributes to apply.
- * @return {Object}
- */
-export default function icon(fontClass, attrs = {}) {
-  attrs.className = 'icon ' + fontClass + ' ' + (attrs.className || '');
-
-  return <i {...attrs} />;
-}

js/src/common/helpers/icon.tsx

@@ -0,0 +1,13 @@
+import * as Mithril from 'mithril';
+
+/**
+ * The `icon` helper displays an icon.
+ *
+ * @param fontClass The full icon class, prefix and the icon’s name.
+ * @param attrs Any other attributes to apply.
+ */
+export default function icon(fontClass: string, attrs: Mithril.Attributes = {}): Mithril.Vnode {
+  attrs.className = 'icon ' + fontClass + ' ' + (attrs.className || '');
+
+  return <i {...attrs} />;
+}

js/src/common/helpers/listItems.js

@@ -2,14 +2,14 @@ import Separator from '../components/Separator';
 import classList from '../utils/classList';
 
 function isSeparator(item) {
-  return item && item.component === Separator;
+  return item.tag === Separator;
 }
 
 function withoutUnnecessarySeparators(items) {
   const newItems = [];
   let prevItem;
 
-  items.forEach((item, i) => {
+  items.filter(Boolean).forEach((item, i) => {
     if (!isSeparator(item) || (prevItem && !isSeparator(prevItem) && i !== items.length - 1)) {
       prevItem = item;
       newItems.push(item);
@@ -30,21 +30,27 @@ export default function listItems(items) {
   if (!(items instanceof Array)) items = [items];
 
   return withoutUnnecessarySeparators(items).map((item) => {
-    const isListItem = item.component && item.component.isListItem;
-    const active = item.component && item.component.isActive && item.component.isActive(item.props);
-    const className = item.props ? item.props.itemClassName : item.itemClassName;
+    const isListItem = item.tag && item.tag.isListItem;
+    const active = item.tag && item.tag.isActive && item.tag.isActive(item.attrs);
+    const className = (item.attrs && item.attrs.itemClassName) || item.itemClassName;
 
     if (isListItem) {
       item.attrs = item.attrs || {};
       item.attrs.key = item.attrs.key || item.itemName;
+      item.key = item.attrs.key;
     }
 
-    return isListItem ? (
+    const node = isListItem ? (
       item
     ) : (
-      <li className={classList([item.itemName ? 'item-' + item.itemName : '', className, active ? 'active' : ''])} key={item.itemName}>
+      <li
+        className={classList([className, item.itemName && `item-${item.itemName}`, active && 'active'])}
+        key={(item.attrs && item.attrs.key) || item.itemName}
+      >
         {item}
       </li>
     );
+
+    return node;
   });
 }

js/src/common/resolvers/DefaultResolver.ts

@@ -0,0 +1,41 @@
+import Mithril from 'mithril';
+
+/**
+ * Generates a route resolver for a given component.
+ * In addition to regular route resolver functionality:
+ * - It provide the current route name as an attr
+ * - It sets a key on the component so a rerender will be triggered on route change.
+ */
+export default class DefaultResolver {
+  component: Mithril.Component;
+  routeName: string;
+
+  constructor(component, routeName) {
+    this.component = component;
+    this.routeName = routeName;
+  }
+
+  /**
+   * When a route change results in a changed key, a full page
+   * rerender occurs. This method can be overriden in subclasses
+   * to prevent rerenders on some route changes.
+   */
+  makeKey() {
+    return this.routeName + JSON.stringify(m.route.param());
+  }
+
+  makeAttrs(vnode) {
+    return {
+      ...vnode.attrs,
+      routeName: this.routeName,
+    };
+  }
+
+  onmatch(args, requestedPath, route) {
+    return this.component;
+  }
+
+  render(vnode) {
+    return [{ ...vnode, attrs: this.makeAttrs(vnode), key: this.makeKey() }];
+  }
+}

js/src/common/states/AlertManagerState.js

@@ -1,50 +0,0 @@
-import Alert from '../components/Alert';
-
-export default class AlertManagerState {
-  constructor() {
-    this.activeAlerts = {};
-    this.alertId = 0;
-  }
-
-  getActiveAlerts() {
-    return this.activeAlerts;
-  }
-
-  /**
-   * Show an Alert in the alerts area.
-   */
-  show(attrs, componentClass = Alert) {
-    // Breaking Change Compliance Warning, Remove in Beta 15.
-    // This is applied to the first argument (attrs) because previously, the alert was passed as the first argument.
-    if (attrs === Alert || attrs instanceof Alert) {
-      // This is duplicated so that if the error is caught, an error message still shows up in the debug console.
-      console.error('The AlertManager can only show Alerts. Whichever extension triggered this alert should be updated to comply with beta 14.');
-      throw new Error('The AlertManager can only show Alerts. Whichever extension triggered this alert should be updated to comply with beta 14.');
-    }
-    // End Change Compliance Warning, Remove in Beta 15
-    this.activeAlerts[++this.alertId] = { attrs, componentClass };
-    m.redraw();
-
-    return this.alertId;
-  }
-
-  /**
-   * Dismiss an alert.
-   */
-  dismiss(key) {
-    if (!key || !(key in this.activeAlerts)) return;
-
-    delete this.activeAlerts[key];
-    m.redraw();
-  }
-
-  /**
-   * Clear all alerts.
-   *
-   * @public
-   */
-  clear() {
-    this.activeAlerts = {};
-    m.redraw();
-  }
-}

js/src/common/states/AlertManagerState.ts

@@ -0,0 +1,80 @@
+import Mithril from 'mithril';
+import Alert, { AlertAttrs } from '../components/Alert';
+
+/**
+ * Returned by `AlertManagerState.show`. Used to dismiss alerts.
+ */
+export type AlertIdentifier = number;
+
+export interface AlertState {
+  componentClass: typeof Alert;
+  attrs: AlertAttrs;
+  children: Mithril.Children;
+}
+
+export default class AlertManagerState {
+  protected activeAlerts: { [id: number]: AlertState } = {};
+  protected alertId = 0;
+
+  getActiveAlerts() {
+    return this.activeAlerts;
+  }
+
+  /**
+   * Show an Alert in the alerts area.
+   *
+   * @returns The alert's ID, which can be used to dismiss the alert.
+   */
+  show(children: Mithril.Children): AlertIdentifier;
+  show(attrs: AlertAttrs, children: Mithril.Children): AlertIdentifier;
+  show(componentClass: Alert, attrs: AlertAttrs, children: Mithril.Children): AlertIdentifier;
+
+  show(arg1: any, arg2?: any, arg3?: any) {
+    // Assigns variables as per the above signatures
+    let componentClass = Alert;
+    let attrs: AlertAttrs = {};
+    let children: Mithril.Children;
+
+    if (arguments.length == 1) {
+      children = arg1 as Mithril.Children;
+    } else if (arguments.length == 2) {
+      attrs = arg1 as AlertAttrs;
+      children = arg2 as Mithril.Children;
+    } else if (arguments.length == 3) {
+      componentClass = arg1 as typeof Alert;
+      attrs = arg2 as AlertAttrs;
+      children = arg3;
+    }
+
+    // Breaking Change Compliance Warning, Remove in Beta 15.
+    // This is applied to the first argument (attrs) because previously, the alert was passed as the first argument.
+    if (attrs === Alert || attrs instanceof Alert) {
+      // This is duplicated so that if the error is caught, an error message still shows up in the debug console.
+      console.error('The AlertManager can only show Alerts. Whichever extension triggered this alert should be updated to comply with beta 14.');
+      throw new Error('The AlertManager can only show Alerts. Whichever extension triggered this alert should be updated to comply with beta 14.');
+    }
+    // End Change Compliance Warning, Remove in Beta 15
+    this.activeAlerts[++this.alertId] = { children, attrs, componentClass };
+    m.redraw();
+
+    return this.alertId;
+  }
+
+  /**
+   * Dismiss an alert.
+   */
+  dismiss(key: AlertIdentifier): void {
+    if (!key || !(key in this.activeAlerts)) return;
+
+    delete this.activeAlerts[key];
+    m.redraw();
+  }
+
+  /**
+   * Clear all alerts.
+   */
+  clear(): void {
+    this.activeAlerts = {};
+    m.redraw();
+  }
+}

js/src/common/states/ModalManagerState.js

@@ -32,7 +32,7 @@ export default class ModalManagerState {
 
     this.modal = { componentClass, attrs };
 
-    m.redraw(true);
+    m.redraw.sync();
   }
 
   /**
@@ -50,7 +50,7 @@ export default class ModalManagerState {
     // ahead.
     this.closeTimeout = setTimeout(() => {
       this.modal = null;
-      m.lazyRedraw();
+      m.redraw();
     });
   }
 }

js/src/common/utils/ScrollListener.js

@@ -58,7 +58,7 @@ export default class ScrollListener {
    */
   start() {
     if (!this.active) {
-      window.addEventListener('scroll', (this.active = this.loop.bind(this)));
+      window.addEventListener('scroll', (this.active = this.loop.bind(this)), { passive: true });
     }
   }
 

js/src/common/utils/Stream.js

@@ -0,0 +1,3 @@
+import Stream from 'mithril/stream';
+
+export default Stream;

js/src/common/utils/SubtreeRetainer.js

@@ -1,20 +1,25 @@
 /**
- * The `SubtreeRetainer` class represents a Mithril virtual DOM subtree. It
- * keeps track of a number of pieces of data, allowing the subtree to be
- * retained if none of them have changed.
+ * The `SubtreeRetainer` class keeps track of a number of pieces of data,
+ * comparing the values of these pieces at every iteration.
+ *
+ * This is useful for preventing redraws to relatively static (or huge)
+ * components whose VDOM only depends on very few values, when none of them
+ * have changed.
  *
  * @example
- * // constructor
+ * // Check two callbacks for changes on each update
  * this.subtree = new SubtreeRetainer(
- *   () => this.props.post.freshness,
+ *   () => this.attrs.post.freshness,
  *   () => this.showing
  * );
- * this.subtree.check(() => this.props.user.freshness);
  *
- * // view
- * this.subtree.retain() || 'expensive expression'
+ * // Add more callbacks to be checked for updates
+ * this.subtree.check(() => this.attrs.user.freshness);
  *
- * @see https://lhorie.github.io/mithril/mithril.html#persisting-dom-elements-across-route-changes
+ * // In a component's onbeforeupdate() method:
+ * return this.subtree.needsRebuild()
+ *
+ * @see https://mithril.js.org/lifecycle-methods.html#onbeforeupdate
  */
 export default class SubtreeRetainer {
   /**
@@ -23,16 +28,19 @@ export default class SubtreeRetainer {
   constructor(...callbacks) {
     this.callbacks = callbacks;
     this.data = {};
+    // Build the initial data, so it is available when calling
+    // needsRebuild from the onbeforeupdate hook.
+    this.needsRebuild();
   }
 
   /**
-   * Return a virtual DOM directive that will retain a subtree if no data has
-   * changed since the last check.
+   * Return whether any data has changed since the last check.
+   * If so, Mithril needs to re-diff the vnode and its children.
    *
-   * @return {Object|false}
+   * @return {boolean}
    * @public
    */
-  retain() {
+  needsRebuild() {
     let needsRebuild = false;
 
     this.callbacks.forEach((callback, i) => {
@@ -44,7 +52,7 @@ export default class SubtreeRetainer {
       }
     });
 
-    return needsRebuild ? false : { subtree: 'retain' };
+    return needsRebuild;
   }
 
   /**
@@ -55,6 +63,8 @@ export default class SubtreeRetainer {
    */
   check(...callbacks) {
     this.callbacks = this.callbacks.concat(callbacks);
+    // Update the data cache when new checks are added.
+    this.needsRebuild();
   }
 
   /**

js/src/common/utils/SuperTextarea.js

@@ -22,6 +22,8 @@ export default class SuperTextarea {
    */
   setValue(value) {
     this.$.val(value).trigger('input');
+
+    this.el.dispatchEvent(new CustomEvent('input', { bubbles: true, cancelable: true }));
   }
 
   /**
@@ -49,8 +51,6 @@ export default class SuperTextarea {
    */
   insertAtCursor(text) {
     this.insertAt(this.el.selectionStart, text);
-
-    this.el.dispatchEvent(new CustomEvent('input', { bubbles: true, cancelable: true }));
   }
 
   /**

js/src/common/utils/abbreviateNumber.ts

@@ -10,7 +10,7 @@ export default function abbreviateNumber(number: number): string {
   if (number >= 1000000) {
     return Math.floor(number / 1000000) + app.translator.trans('core.lib.number_suffix.mega_text');
   } else if (number >= 1000) {
-    return Math.floor(number / 1000) + app.translator.trans('core.lib.number_suffix.kilo_text');
+    return (number / 1000).toFixed(1) + app.translator.trans('core.lib.number_suffix.kilo_text');
   } else {
     return number.toString();
   }

js/src/common/utils/extractText.js

@@ -8,7 +8,7 @@ export default function extractText(vdom) {
   if (vdom instanceof Array) {
     return vdom.map((element) => extractText(element)).join('');
   } else if (typeof vdom === 'object' && vdom !== null) {
-    return extractText(vdom.children);
+    return vdom.children ? extractText(vdom.children) : vdom.text;
   } else {
     return vdom;
   }

js/src/common/utils/humanTime.ts

@@ -1,3 +1,6 @@
+import dayjs from 'dayjs';
+import 'dayjs/plugin/relativeTime';
+
 /**
  * The `humanTime` utility converts a date to a localized, human-readable time-
  * ago string.

js/src/common/utils/mapRoutes.js

@@ -1,8 +1,11 @@
+import DefaultResolver from '../resolvers/DefaultResolver';
+
 /**
  * The `mapRoutes` utility converts a map of named application routes into a
- * format that can be understood by Mithril.
+ * format that can be understood by Mithril, and wraps them in route resolvers
+ * to provide each route with the current route name.
  *
- * @see https://lhorie.github.io/mithril/mithril.route.html#defining-routes
+ * @see https://mithril.js.org/route.html#signature
  * @param {Object} routes
  * @param {String} [basePath]
  * @return {Object}
@@ -10,12 +13,17 @@
 export default function mapRoutes(routes, basePath = '') {
   const map = {};
 
-  for (const key in routes) {
-    const route = routes[key];
+  for (const routeName in routes) {
+    const route = routes[routeName];
 
-    if (route.component) route.component.props.routeName = key;
-
-    map[basePath + route.path] = route.component;
+    if ('resolver' in route) {
+      map[basePath + route.path] = route.resolver;
+    } else if ('component' in route) {
+      const resolverClass = 'resolverClass' in route ? route.resolverClass : DefaultResolver;
+      map[basePath + route.path] = new resolverClass(route.component, routeName);
+    } else {
+      throw new Error(`Either a resolver or a component must be provided for the route [${routeName}]`);
+    }
   }
 
   return map;

js/src/common/utils/patchMithril.js

@@ -1,45 +1,44 @@
-import Component from '../Component';
+import withAttr from './withAttr';
+import Stream from './Stream';
+
+let deprecatedMPropWarned = false;
+let deprecatedMWithAttrWarned = false;
 
 export default function patchMithril(global) {
-  const mo = global.m;
+  const defaultMithril = global.m;
 
-  const m = function (comp, ...args) {
-    if (comp.prototype && comp.prototype instanceof Component) {
-      let children = args.slice(1);
-      if (children.length === 1 && Array.isArray(children[0])) {
-        children = children[0];
-      }
+  const modifiedMithril = function (comp, ...args) {
+    const node = defaultMithril.apply(this, arguments);
 
-      return comp.component(args[0], children);
-    }
-
-    const node = mo.apply(this, arguments);
+    if (!node.attrs) node.attrs = {};
 
+    // Allows the use of the bidi attr.
     if (node.attrs.bidi) {
-      m.bidi(node, node.attrs.bidi);
-    }
-
-    if (node.attrs.route) {
-      node.attrs.href = node.attrs.route;
-      node.attrs.config = m.route;
-
-      delete node.attrs.route;
+      modifiedMithril.bidi(node, node.attrs.bidi);
     }
 
     return node;
   };
 
-  Object.keys(mo).forEach((key) => (m[key] = mo[key]));
+  Object.keys(defaultMithril).forEach((key) => (modifiedMithril[key] = defaultMithril[key]));
 
-  /**
-   * Redraw only if not in the middle of a computation (e.g. a route change).
-   *
-   * @return {void}
-   */
-  m.lazyRedraw = function () {
-    m.startComputation();
-    m.endComputation();
+  // BEGIN DEPRECATED MITHRIL 2 BC LAYER
+  modifiedMithril.prop = function (...args) {
+    if (!deprecatedMPropWarned) {
+      deprecatedMPropWarned = true;
+      console.warn('m.prop() is deprecated, please use the Stream util (flarum/utils/Streams) instead.');
+    }
+    return Stream.bind(this)(...args);
   };
 
-  global.m = m;
+  modifiedMithril.withAttr = function (...args) {
+    if (!deprecatedMWithAttrWarned) {
+      deprecatedMWithAttrWarned = true;
+      console.warn("m.withAttr() is deprecated, please use flarum's withAttr util (flarum/utils/withAttr) instead.");
+    }
+    return withAttr.bind(this)(...args);
+  };
+  // END DEPRECATED MITHRIL 2 BC LAYER
+
+  global.m = modifiedMithril;
 }

js/src/common/utils/setRouteWithForcedRefresh.ts

@@ -0,0 +1,15 @@
+import Mithril from 'mithril';
+
+/**
+ * Mithril 2 does not completely rerender the page if a route change leads to the same route
+ * (or the same component handling a different route). This util calls m.route.set, forcing a reonit.
+ *
+ * @see https://mithril.js.org/route.html#key-parameter
+ */
+export default function setRouteWithForcedRefresh(route: string, params = null, options: Mithril.RouteOptions = {}) {
+  const newOptions = { ...options };
+  newOptions.state = newOptions.state || {};
+  newOptions.state.key = Date.now();
+
+  m.route.set(route, params, newOptions);
+}

js/src/common/utils/withAttr.ts

@@ -0,0 +1,15 @@
+/**
+ * An event handler factory that makes it simpler to implement data binding
+ * for component event listeners.
+ *
+ * The handler created by this factory passes the DOM element's attribute
+ * identified by the first argument to the callback (usually a bidirectional
+ * Mithril stream: https://mithril.js.org/stream.html#bidirectional-bindings).
+ *
+ * Replaces m.withAttr for Mithril 2.0.
+ * @see https://mithril.js.org/archive/v0.2.5/mithril.withAttr.html
+ */
+export default (key: string, cb: Function) =>
+  function (this: Element) {
+    cb(this.getAttribute(key) || this[key]);
+  };

js/src/forum/ForumApplication.js

@@ -115,17 +115,19 @@ export default class ForumApplication extends Application {
     this.routes[defaultAction].path = '/';
     this.history.push(defaultAction, this.translator.trans('core.forum.header.back_to_index_tooltip'), '/');
 
-    m.mount(document.getElementById('app-navigation'), Navigation.component({ className: 'App-backControl', drawer: true }));
-    m.mount(document.getElementById('header-navigation'), Navigation.component());
-    m.mount(document.getElementById('header-primary'), HeaderPrimary.component());
-    m.mount(document.getElementById('header-secondary'), HeaderSecondary.component());
-    m.mount(document.getElementById('composer'), Composer.component({ state: this.composer }));
-
     this.pane = new Pane(document.getElementById('app'));
 
-    m.route.mode = 'pathname';
+    m.route.prefix = '';
     super.mount(this.forum.attribute('basePath'));
 
+    // We mount navigation and header components after the page, so components
+    // like the back button can access the updated state when rendering.
+    m.mount(document.getElementById('app-navigation'), { view: () => Navigation.component({ className: 'App-backControl', drawer: true }) });
+    m.mount(document.getElementById('header-navigation'), Navigation);
+    m.mount(document.getElementById('header-primary'), HeaderPrimary);
+    m.mount(document.getElementById('header-secondary'), HeaderSecondary);
+    m.mount(document.getElementById('composer'), { view: () => Composer.component({ state: this.composer }) });
+
     alertEmailConfirmation(this);
 
     // Route the home link back home when clicked. We do not want it to register
@@ -161,8 +163,8 @@ export default class ForumApplication extends Application {
    * will be reloaded. Otherwise, a SignUpModal will be opened, prefilled
    * with the provided details.
    *
-   * @param {Object} payload A dictionary of props to pass into the sign up
-   *     modal. A truthy `loggedIn` prop indicates that the user has logged
+   * @param {Object} payload A dictionary of attrs to pass into the sign up
+   *     modal. A truthy `loggedIn` attr indicates that the user has logged
    *     in, and thus the page is reloaded.
    * @public
    */

js/src/forum/compat.js

@@ -3,16 +3,18 @@ import compat from '../common/compat';
 import PostControls from './utils/PostControls';
 import KeyboardNavigatable from './utils/KeyboardNavigatable';
 import slidable from './utils/slidable';
-import affixSidebar from './utils/affixSidebar';
 import History from './utils/History';
 import DiscussionControls from './utils/DiscussionControls';
 import alertEmailConfirmation from './utils/alertEmailConfirmation';
 import UserControls from './utils/UserControls';
 import Pane from './utils/Pane';
+import ComposerState from './states/ComposerState';
 import DiscussionListState from './states/DiscussionListState';
 import GlobalSearchState from './states/GlobalSearchState';
 import NotificationListState from './states/NotificationListState';
+import PostStreamState from './states/PostStreamState';
 import SearchState from './states/SearchState';
+import AffixedSidebar from './components/AffixedSidebar';
 import DiscussionPage from './components/DiscussionPage';
 import LogInModal from './components/LogInModal';
 import ComposerBody from './components/ComposerBody';
@@ -59,6 +61,7 @@ import NotificationList from './components/NotificationList';
 import WelcomeHero from './components/WelcomeHero';
 import SignUpModal from './components/SignUpModal';
 import CommentPost from './components/CommentPost';
+import ComposerPostPreview from './components/ComposerPostPreview';
 import ReplyComposer from './components/ReplyComposer';
 import NotificationsPage from './components/NotificationsPage';
 import PostStreamScrubber from './components/PostStreamScrubber';
@@ -68,6 +71,7 @@ import Search from './components/Search';
 import DiscussionListItem from './components/DiscussionListItem';
 import LoadingPost from './components/LoadingPost';
 import PostsUserPage from './components/PostsUserPage';
+import DiscussionPageResolver from './resolvers/DiscussionPageResolver';
 import routes from './routes';
 import ForumApplication from './ForumApplication';
 
@@ -75,16 +79,18 @@ export default Object.assign(compat, {
   'utils/PostControls': PostControls,
   'utils/KeyboardNavigatable': KeyboardNavigatable,
   'utils/slidable': slidable,
-  'utils/affixSidebar': affixSidebar,
   'utils/History': History,
   'utils/DiscussionControls': DiscussionControls,
   'utils/alertEmailConfirmation': alertEmailConfirmation,
   'utils/UserControls': UserControls,
   'utils/Pane': Pane,
+  'states/ComposerState': ComposerState,
   'states/DiscussionListState': DiscussionListState,
   'states/GlobalSearchState': GlobalSearchState,
   'states/NotificationListState': NotificationListState,
+  'states/PostStreamState': PostStreamState,
   'states/SearchState': SearchState,
+  'components/AffixedSidebar': AffixedSidebar,
   'components/DiscussionPage': DiscussionPage,
   'components/LogInModal': LogInModal,
   'components/ComposerBody': ComposerBody,
@@ -131,6 +137,7 @@ export default Object.assign(compat, {
   'components/WelcomeHero': WelcomeHero,
   'components/SignUpModal': SignUpModal,
   'components/CommentPost': CommentPost,
+  'components/ComposerPostPreview': ComposerPostPreview,
   'components/ReplyComposer': ReplyComposer,
   'components/NotificationsPage': NotificationsPage,
   'components/PostStreamScrubber': PostStreamScrubber,
@@ -140,6 +147,7 @@ export default Object.assign(compat, {
   'components/DiscussionListItem': DiscussionListItem,
   'components/LoadingPost': LoadingPost,
   'components/PostsUserPage': PostsUserPage,
+  'resolvers/DiscussionPageResolver': DiscussionPageResolver,
   routes: routes,
   ForumApplication: ForumApplication,
 });

js/src/forum/components/AffixedSidebar.js

@@ -0,0 +1,51 @@
+import Component from '../../common/Component';
+
+/**
+ * The `AffixedSidebar` component uses Bootstrap's "affix" plugin to keep a
+ * sidebar navigation at the top of the viewport when scrolling.
+ *
+ * ### Children
+ *
+ * The component must wrap an element that itself wraps an <ul> element, which
+ * will be "affixed".
+ *
+ * @see https://getbootstrap.com/docs/3.4/javascript/#affix
+ */
+export default class AffixedSidebar extends Component {
+  view(vnode) {
+    return vnode.children[0];
+  }
+
+  oncreate(vnode) {
+    super.oncreate(vnode);
+
+    // Register the affix plugin to execute on every window resize (and trigger)
+    this.boundOnresize = this.onresize.bind(this);
+    $(window).on('resize', this.boundOnresize).resize();
+  }
+
+  onremove() {
+    $(window).off('resize', this.boundOnresize);
+  }
+
+  onresize() {
+    const $sidebar = this.$();
+    const $header = $('#header');
+    const $footer = $('#footer');
+    const $affixElement = $sidebar.find('> ul');
+
+    $(window).off('.affix');
+    $affixElement.removeClass('affix affix-top affix-bottom').removeData('bs.affix');
+
+    // Don't affix the sidebar if it is taller than the viewport (otherwise
+    // there would be no way to scroll through its content).
+    if ($sidebar.outerHeight(true) > $(window).height() - $header.outerHeight(true)) return;
+
+    $affixElement.affix({
+      offset: {
+        top: () => $sidebar.offset().top - $header.outerHeight(true) - parseInt($sidebar.css('margin-top'), 10),
+        bottom: () => (this.bottom = $footer.outerHeight(true)),
+      },
+    });
+  }
+}

js/src/forum/components/AvatarEditor.js

@@ -3,6 +3,7 @@ import avatar from '../../common/helpers/avatar';
 import icon from '../../common/helpers/icon';
 import listItems from '../../common/helpers/listItems';
 import ItemList from '../../common/utils/ItemList';
+import classList from '../../common/utils/classList';
 import Button from '../../common/components/Button';
 import LoadingIndicator from '../../common/components/LoadingIndicator';
 
@@ -10,13 +11,15 @@ import LoadingIndicator from '../../common/components/LoadingIndicator';
  * The `AvatarEditor` component displays a user's avatar along with a dropdown
  * menu which allows the user to upload/remove the avatar.
  *
- * ### Props
+ * ### Attrs
  *
  * - `className`
  * - `user`
  */
 export default class AvatarEditor extends Component {
-  init() {
+  oninit(vnode) {
+    super.oninit(vnode);
+
     /**
      * Whether or not an avatar upload is in progress.
      *
@@ -32,17 +35,11 @@ export default class AvatarEditor extends Component {
     this.isDraggedOver = false;
   }
 
-  static initProps(props) {
-    super.initProps(props);
-
-    props.className = props.className || '';
-  }
-
   view() {
-    const user = this.props.user;
+    const user = this.attrs.user;
 
     return (
-      <div className={'AvatarEditor Dropdown ' + this.props.className + (this.loading ? ' loading' : '') + (this.isDraggedOver ? ' dragover' : '')}>
+      <div className={classList(['AvatarEditor', 'Dropdown', this.attrs.className, this.loading && 'loading', this.isDraggedOver && 'dragover'])}>
         {avatar(user)}
         <a
           className={user.avatarUrl() ? 'Dropdown-toggle' : 'Dropdown-toggle AvatarEditor--noAvatar'}
@@ -55,7 +52,7 @@ export default class AvatarEditor extends Component {
           ondragend={this.disableDragover.bind(this)}
           ondrop={this.dropUpload.bind(this)}
         >
-          {this.loading ? LoadingIndicator.component() : user.avatarUrl() ? icon('fas fa-pencil-alt') : icon('fas fa-plus-circle')}
+          {this.loading ? <LoadingIndicator /> : user.avatarUrl() ? icon('fas fa-pencil-alt') : icon('fas fa-plus-circle')}
         </a>
         <ul className="Dropdown-menu Menu">{listItems(this.controlItems().toArray())}</ul>
       </div>
@@ -72,20 +69,16 @@ export default class AvatarEditor extends Component {
 
     items.add(
       'upload',
-      Button.component({
-        icon: 'fas fa-upload',
-        children: app.translator.trans('core.forum.user.avatar_upload_button'),
-        onclick: this.openPicker.bind(this),
-      })
+      <Button icon="fas fa-upload" onclick={this.openPicker.bind(this)}>
+        {app.translator.trans('core.forum.user.avatar_upload_button')}
+      </Button>
     );
 
     items.add(
       'remove',
-      Button.component({
-        icon: 'fas fa-times',
-        children: app.translator.trans('core.forum.user.avatar_remove_button'),
-        onclick: this.remove.bind(this),
-      })
+      <Button icon="fas fa-times" onclick={this.remove.bind(this)}>
+        {app.translator.trans('core.forum.user.avatar_remove_button')}
+      </Button>
     );
 
     return items;
@@ -134,7 +127,7 @@ export default class AvatarEditor extends Component {
    * @param {Event} e
    */
   quickUpload(e) {
-    if (!this.props.user.avatarUrl()) {
+    if (!this.attrs.user.avatarUrl()) {
       e.preventDefault();
       e.stopPropagation();
       this.openPicker();
@@ -149,7 +142,6 @@ export default class AvatarEditor extends Component {
 
     // Create a hidden HTML input element and click on it so the user can select
     // an avatar file. Once they have, we will upload it via the API.
-    const user = this.props.user;
     const $input = $('<input type="file">');
 
     $input
@@ -169,7 +161,7 @@ export default class AvatarEditor extends Component {
   upload(file) {
     if (this.loading) return;
 
-    const user = this.props.user;
+    const user = this.attrs.user;
     const data = new FormData();
     data.append('avatar', file);
 
@@ -179,9 +171,9 @@ export default class AvatarEditor extends Component {
     app
       .request({
         method: 'POST',
-        url: app.forum.attribute('apiUrl') + '/users/' + user.id() + '/avatar',
+        url: `${app.forum.attribute('apiUrl')}/users/${user.id()}/avatar`,
         serialize: (raw) => raw,
-        data,
+        body: data,
       })
       .then(this.success.bind(this), this.failure.bind(this));
   }
@@ -190,7 +182,7 @@ export default class AvatarEditor extends Component {
    * Remove the user's avatar.
    */
   remove() {
-    const user = this.props.user;
+    const user = this.attrs.user;
 
     this.loading = true;
     m.redraw();
@@ -198,7 +190,7 @@ export default class AvatarEditor extends Component {
     app
       .request({
         method: 'DELETE',
-        url: app.forum.attribute('apiUrl') + '/users/' + user.id() + '/avatar',
+        url: `${app.forum.attribute('apiUrl')}/users/${user.id()}/avatar`,
       })
       .then(this.success.bind(this), this.failure.bind(this));
   }
@@ -212,7 +204,7 @@ export default class AvatarEditor extends Component {
    */
   success(response) {
     app.store.pushPayload(response);
-    delete this.props.user.avatarColor;
+    delete this.attrs.user.avatarColor;
 
     this.loading = false;
     m.redraw();

js/src/forum/components/ChangeEmailModal.js

@@ -1,13 +1,14 @@
 import Modal from '../../common/components/Modal';
 import Button from '../../common/components/Button';
+import Stream from '../../common/utils/Stream';
 
 /**
  * The `ChangeEmailModal` component shows a modal dialog which allows the user
  * to change their email address.
  */
 export default class ChangeEmailModal extends Modal {
-  init() {
-    super.init();
+  oninit(vnode) {
+    super.oninit(vnode);
 
     /**
      * Whether or not the email has been changed successfully.
@@ -21,14 +22,14 @@ export default class ChangeEmailModal extends Modal {
      *
      * @type {function}
      */
-    this.email = m.prop(app.session.user.email());
+    this.email = Stream(app.session.user.email());
 
     /**
      * The value of the password input.
      *
      * @type {function}
      */
-    this.password = m.prop('');
+    this.password = Stream('');
   }
 
   className() {
@@ -81,12 +82,14 @@ export default class ChangeEmailModal extends Modal {
             />
           </div>
           <div className="Form-group">
-            {Button.component({
-              className: 'Button Button--primary Button--block',
-              type: 'submit',
-              loading: this.loading,
-              children: app.translator.trans('core.forum.change_email.submit_button'),
-            })}
+            {Button.component(
+              {
+                className: 'Button Button--primary Button--block',
+                type: 'submit',
+                loading: this.loading,
+              },
+              app.translator.trans('core.forum.change_email.submit_button')
+            )}
           </div>
         </div>
       </div>
@@ -122,7 +125,7 @@ export default class ChangeEmailModal extends Modal {
 
   onerror(error) {
     if (error.status === 401) {
-      error.alert.children = app.translator.trans('core.forum.change_email.incorrect_password_message');
+      error.alert.content = app.translator.trans('core.forum.change_email.incorrect_password_message');
     }
 
     super.onerror(error);

js/src/forum/components/ChangePasswordModal.js

@@ -20,12 +20,14 @@ export default class ChangePasswordModal extends Modal {
         <div className="Form Form--centered">
           <p className="helpText">{app.translator.trans('core.forum.change_password.text')}</p>
           <div className="Form-group">
-            {Button.component({
-              className: 'Button Button--primary Button--block',
-              type: 'submit',
-              loading: this.loading,
-              children: app.translator.trans('core.forum.change_password.send_button'),
-            })}
+            {Button.component(
+              {
+                className: 'Button Button--primary Button--block',
+                type: 'submit',
+                loading: this.loading,
+              },
+              app.translator.trans('core.forum.change_password.send_button')
+            )}
           </div>
         </div>
       </div>
@@ -41,7 +43,7 @@ export default class ChangePasswordModal extends Modal {
       .request({
         method: 'POST',
         url: app.forum.attribute('apiUrl') + '/forgot',
-        data: { email: app.session.user.email() },
+        body: { email: app.session.user.email() },
       })
       .then(this.hide.bind(this), this.loaded.bind(this));
   }

js/src/forum/components/CommentPost.js

@@ -1,5 +1,3 @@
-/*global s9e, hljs*/
-
 import Post from './Post';
 import classList from '../../common/utils/classList';
 import PostUser from './PostUser';
@@ -9,19 +7,20 @@ import EditPostComposer from './EditPostComposer';
 import ItemList from '../../common/utils/ItemList';
 import listItems from '../../common/helpers/listItems';
 import Button from '../../common/components/Button';
+import ComposerPostPreview from './ComposerPostPreview';
 
 /**
  * The `CommentPost` component displays a standard `comment`-typed post. This
  * includes a number of item lists (controls, header, and footer) surrounding
  * the post's HTML content.
  *
- * ### Props
+ * ### Attrs
  *
  * - `post`
  */
 export default class CommentPost extends Post {
-  init() {
-    super.init();
+  oninit(vnode) {
+    super.oninit(vnode);
 
     /**
      * If the post has been hidden, then this flag determines whether or not its
@@ -41,48 +40,59 @@ export default class CommentPost extends Post {
 
     this.subtree.check(
       () => this.cardVisible,
-      () => this.isEditing()
+      () => this.isEditing(),
+      () => this.revealContent
     );
   }
 
   content() {
-    // Note: we avoid using JSX for the <ul> below because it results in some
-    // weirdness in Mithril.js 0.1.x (see flarum/core#975). This workaround can
-    // be reverted when we upgrade to Mithril 1.0.
-    return super
-      .content()
-      .concat([
-        <header className="Post-header">{m('ul', listItems(this.headerItems().toArray()))}</header>,
-        <div className="Post-body">
-          {this.isEditing() ? <div className="Post-preview" config={this.configPreview.bind(this)} /> : m.trust(this.props.post.contentHtml())}
-        </div>,
-      ]);
+    return super.content().concat([
+      <header className="Post-header">
+        <ul>{listItems(this.headerItems().toArray())}</ul>
+      </header>,
+      <div className="Post-body">
+        {this.isEditing() ? <ComposerPostPreview className="Post-preview" composer={app.composer} /> : m.trust(this.attrs.post.contentHtml())}
+      </div>,
+    ]);
   }
 
-  config(isInitialized, context) {
-    super.config(...arguments);
-
-    const contentHtml = this.isEditing() ? '' : this.props.post.contentHtml();
+  refreshContent() {
+    const contentHtml = this.isEditing() ? '' : this.attrs.post.contentHtml();
 
     // If the post content has changed since the last render, we'll run through
     // all of the <script> tags in the content and evaluate them. This is
     // necessary because TextFormatter outputs them for e.g. syntax highlighting.
-    if (context.contentHtml !== contentHtml) {
+    if (this.contentHtml !== contentHtml) {
       this.$('.Post-body script').each(function () {
-        eval.call(window, $(this).text());
+        const script = document.createElement('script');
+        script.textContent = this.textContent;
+        Array.from(this.attributes).forEach((attr) => script.setAttribute(attr.name, attr.value));
+        this.parentNode.replaceChild(script, this);
       });
     }
 
-    context.contentHtml = contentHtml;
+    this.contentHtml = contentHtml;
+  }
+
+  oncreate(vnode) {
+    super.oncreate(vnode);
+
+    this.refreshContent();
+  }
+
+  onupdate(vnode) {
+    super.onupdate(vnode);
+
+    this.refreshContent();
   }
 
   isEditing() {
-    return app.composer.bodyMatches(EditPostComposer, { post: this.props.post });
+    return app.composer.bodyMatches(EditPostComposer, { post: this.attrs.post });
   }
 
-  attrs() {
-    const post = this.props.post;
-    const attrs = super.attrs();
+  elementAttrs() {
+    const post = this.attrs.post;
+    const attrs = super.elementAttrs();
 
     attrs.className =
       (attrs.className || '') +
@@ -98,27 +108,6 @@ export default class CommentPost extends Post {
     return attrs;
   }
 
-  configPreview(element, isInitialized, context) {
-    if (isInitialized) return;
-
-    // Every 50ms, if the composer content has changed, then update the post's
-    // body with a preview.
-    let preview;
-    const updatePreview = () => {
-      const content = app.composer.fields.content();
-
-      if (preview === content) return;
-
-      preview = content;
-
-      s9e.TextFormatter.preview(preview || '', element);
-    };
-    updatePreview();
-
-    const updateInterval = setInterval(updatePreview, 50);
-    context.onunload = () => clearInterval(updateInterval);
-  }
-
   /**
    * Toggle the visibility of a hidden post's content.
    */
@@ -133,7 +122,7 @@ export default class CommentPost extends Post {
    */
   headerItems() {
     const items = new ItemList();
-    const post = this.props.post;
+    const post = this.attrs.post;
 
     items.add(
       'user',

js/src/forum/components/Composer.js

@@ -11,13 +11,15 @@ import ComposerState from '../states/ComposerState';
  * `show`, `hide`, `close`, `minimize`, `fullScreen`, and `exitFullScreen`.
  */
 export default class Composer extends Component {
-  init() {
+  oninit(vnode) {
+    super.oninit(vnode);
+
     /**
      * The composer's "state".
      *
      * @type {ComposerState}
      */
-    this.state = this.props.state;
+    this.state = this.attrs.state;
 
     /**
      * Whether or not the composer currently has focus.
@@ -45,7 +47,7 @@ export default class Composer extends Component {
 
     return (
       <div className={'Composer ' + classList(classes)}>
-        <div className="Composer-handle" config={this.configHandle.bind(this)} />
+        <div className="Composer-handle" oncreate={this.configHandle.bind(this)} />
         <ul className="Composer-controls">{listItems(this.controlItems().toArray())}</ul>
         <div className="Composer-content" onclick={showIfMinimized}>
           {body.componentClass ? body.componentClass.component({ ...body.attrs, composer: this.state, disabled: classes.minimized }) : ''}
@@ -54,7 +56,7 @@ export default class Composer extends Component {
     );
   }
 
-  config(isInitialized, context) {
+  onupdate() {
     if (this.state.position === this.prevPosition) {
       // Set the height of the Composer element and its contents on each redraw,
       // so that they do not lose it if their DOM elements are recreated.
@@ -64,12 +66,10 @@ export default class Composer extends Component {
 
       this.prevPosition = this.state.position;
     }
+  }
 
-    if (isInitialized) return;
-
-    // Since this component is a part of the global UI that persists between
-    // routes, we will flag the DOM to be retained across route changes.
-    context.retain = true;
+  oncreate(vnode) {
+    super.oncreate(vnode);
 
     this.initializeHeight();
     this.$().hide().css('bottom', -this.state.computedHeight());
@@ -82,38 +82,33 @@ export default class Composer extends Component {
     });
 
     // When the escape key is pressed on any inputs, close the composer.
-    this.$().on('keydown', ':input', 'esc', () => this.close());
+    this.$().on('keydown', ':input', 'esc', () => this.state.close());
 
-    const handlers = {};
+    this.handlers = {};
 
     $(window)
-      .on('resize', (handlers.onresize = this.updateHeight.bind(this)))
+      .on('resize', (this.handlers.onresize = this.updateHeight.bind(this)))
       .resize();
 
     $(document)
-      .on('mousemove', (handlers.onmousemove = this.onmousemove.bind(this)))
-      .on('mouseup', (handlers.onmouseup = this.onmouseup.bind(this)));
+      .on('mousemove', (this.handlers.onmousemove = this.onmousemove.bind(this)))
+      .on('mouseup', (this.handlers.onmouseup = this.onmouseup.bind(this)));
+  }
 
-    context.onunload = () => {
-      $(window).off('resize', handlers.onresize);
+  onremove() {
+    $(window).off('resize', this.handlers.onresize);
 
-      $(document).off('mousemove', handlers.onmousemove).off('mouseup', handlers.onmouseup);
-    };
+    $(document).off('mousemove', this.handlers.onmousemove).off('mouseup', this.handlers.onmouseup);
   }
 
   /**
    * Add the necessary event handlers to the composer's handle so that it can
    * be used to resize the composer.
-   *
-   * @param {DOMElement} element
-   * @param {Boolean} isInitialized
    */
-  configHandle(element, isInitialized) {
-    if (isInitialized) return;
-
+  configHandle(vnode) {
     const composer = this;
 
-    $(element)
+    $(vnode.dom)
       .css('cursor', 'row-resize')
       .bind('dragstart mousedown', (e) => e.preventDefault())
       .mousedown(function (e) {

js/src/forum/components/ComposerBody.js

@@ -11,7 +11,7 @@ import ItemList from '../../common/utils/ItemList';
  * composer. Subclasses should implement the `onsubmit` method and override
  * `headerTimes`.
  *
- * ### Props
+ * ### Attrs
  *
  * - `composer`
  * - `originalContent`
@@ -24,8 +24,10 @@ import ItemList from '../../common/utils/ItemList';
  * @abstract
  */
 export default class ComposerBody extends Component {
-  init() {
-    this.composer = this.props.composer;
+  oninit(vnode) {
+    super.oninit(vnode);
+
+    this.composer = this.attrs.composer;
 
     /**
      * Whether or not the component is loading.
@@ -37,11 +39,11 @@ export default class ComposerBody extends Component {
     // Let the composer state know to ask for confirmation under certain
     // circumstances, if the body supports / requires it and has a corresponding
     // confirmation question to ask.
-    if (this.props.confirmExit) {
-      this.composer.preventClosingWhen(() => this.hasChanges(), this.props.confirmExit);
+    if (this.attrs.confirmExit) {
+      this.composer.preventClosingWhen(() => this.hasChanges(), this.attrs.confirmExit);
     }
 
-    this.composer.fields.content(this.props.originalContent || '');
+    this.composer.fields.content(this.attrs.originalContent || '');
 
     /**
      * @deprecated BC layer, remove in Beta 15.
@@ -53,15 +55,15 @@ export default class ComposerBody extends Component {
   view() {
     return (
       <ConfirmDocumentUnload when={this.hasChanges.bind(this)}>
-        <div className={'ComposerBody ' + (this.props.className || '')}>
-          {avatar(this.props.user, { className: 'ComposerBody-avatar' })}
+        <div className={'ComposerBody ' + (this.attrs.className || '')}>
+          {avatar(this.attrs.user, { className: 'ComposerBody-avatar' })}
           <div className="ComposerBody-content">
             <ul className="ComposerBody-header">{listItems(this.headerItems().toArray())}</ul>
             <div className="ComposerBody-editor">
               {TextEditor.component({
-                submitLabel: this.props.submitLabel,
-                placeholder: this.props.placeholder,
-                disabled: this.loading || this.props.disabled,
+                submitLabel: this.attrs.submitLabel,
+                placeholder: this.attrs.placeholder,
+                disabled: this.loading || this.attrs.disabled,
                 composer: this.composer,
                 preview: this.jumpToPreview && this.jumpToPreview.bind(this),
                 onchange: this.composer.fields.content,
@@ -84,7 +86,7 @@ export default class ComposerBody extends Component {
   hasChanges() {
     const content = this.composer.fields.content();
 
-    return content && content !== this.props.originalContent;
+    return content && content !== this.attrs.originalContent;
   }
 
   /**

js/src/forum/components/ComposerButton.js

@@ -5,9 +5,9 @@ import Button from '../../common/components/Button';
  * controls.
  */
 export default class ComposerButton extends Button {
-  static initProps(props) {
-    super.initProps(props);
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
 
-    props.className = props.className || 'Button Button--icon Button--link';
+    attrs.className = attrs.className || 'Button Button--icon Button--link';
   }
 }

js/src/forum/components/ComposerPostPreview.js

@@ -0,0 +1,54 @@
+/*global s9e*/
+
+import Component from '../../common/Component';
+
+/**
+ * The `ComposerPostPreview` component renders Markdown as HTML using the
+ * TextFormatter library, polling a data source for changes every 50ms. This is
+ * done to prevent expensive redraws on e.g. every single keystroke, while
+ * still retaining the perception of live updates for the user.
+ *
+ * ### Attrs
+ *
+ * - `composer` The state of the composer controlling this preview.
+ * - `className` A CSS class for the element surrounding the preview.
+ * - `surround` A callback that can execute code before and after re-render, e.g. for scroll anchoring.
+ */
+export default class ComposerPostPreview extends Component {
+  static initAttrs(attrs) {
+    attrs.className = attrs.className || '';
+    attrs.surround = attrs.surround || ((preview) => preview());
+  }
+
+  view() {
+    return <div className={this.attrs.className} />;
+  }
+
+  oncreate(vnode) {
+    super.oncreate(vnode);
+
+    // Every 50ms, if the composer content has changed, then update the post's
+    // body with a preview.
+    let preview;
+    const updatePreview = () => {
+      // Since we're polling, the composer may have been closed in the meantime,
+      // so we bail in that case.
+      if (!this.attrs.composer.isVisible()) return;
+
+      const content = this.attrs.composer.fields.content();
+
+      if (preview === content) return;
+
+      preview = content;
+
+      this.attrs.surround(() => s9e.TextFormatter.preview(preview || '', vnode.dom));
+    };
+    updatePreview();
+
+    this.updateInterval = setInterval(updatePreview, 50);
+  }
+
+  onremove() {
+    clearInterval(this.updateInterval);
+  }
+}

js/src/forum/components/DiscussionComposer.js

@@ -1,5 +1,6 @@
 import ComposerBody from './ComposerBody';
 import extractText from '../../common/utils/extractText';
+import Stream from '../../common/utils/Stream';
 
 /**
  * The `DiscussionComposer` component displays the composer content for starting
@@ -7,16 +8,26 @@ import extractText from '../../common/utils/extractText';
  * enter the title of their discussion. It also overrides the `submit` and
  * `willExit` actions to account for the title.
  *
- * ### Props
+ * ### Attrs
  *
- * - All of the props for ComposerBody
+ * - All of the attrs for ComposerBody
  * - `titlePlaceholder`
  */
 export default class DiscussionComposer extends ComposerBody {
-  init() {
-    super.init();
+  static initAttrs(attrs) {
+    super.initAttrs(attrs);
 
-    this.composer.fields.title = this.composer.fields.title || m.prop('');
+    attrs.placeholder = attrs.placeholder || extractText(app.translator.trans('core.forum.composer_discussion.body_placeholder'));
+    attrs.submitLabel = attrs.submitLabel || app.translator.trans('core.forum.composer_discussion.submit_button');
+    attrs.confirmExit = attrs.confirmExit || extractText(app.translator.trans('core.forum.composer_discussion.discard_confirmation'));
+    attrs.titlePlaceholder = attrs.titlePlaceholder || extractText(app.translator.trans('core.forum.composer_discussion.title_placeholder'));
+    attrs.className = 'ComposerBody--discussion';
+  }
+
+  oninit(vnode) {
+    super.oninit(vnode);
+
+    this.composer.fields.title = this.composer.fields.title || Stream('');
 
     /**
      * The value of the title input.
@@ -26,16 +37,6 @@ export default class DiscussionComposer extends ComposerBody {
     this.title = this.composer.fields.title;
   }
 
-  static initProps(props) {
-    super.initProps(props);
-
-    props.placeholder = props.placeholder || extractText(app.translator.trans('core.forum.composer_discussion.body_placeholder'));
-    props.submitLabel = props.submitLabel || app.translator.trans('core.forum.composer_discussion.submit_button');
-    props.confirmExit = props.confirmExit || extractText(app.translator.trans('core.forum.composer_discussion.discard_confirmation'));
-    props.titlePlaceholder = props.titlePlaceholder || extractText(app.translator.trans('core.forum.composer_discussion.title_placeholder'));
-    props.className = 'ComposerBody--discussion';
-  }
-
   headerItems() {
     const items = super.headerItems();
 
@@ -46,10 +47,9 @@ export default class DiscussionComposer extends ComposerBody {
       <h3>
         <input
           className="FormControl"
-          value={this.title()}
-          oninput={m.withAttr('value', this.title)}
-          placeholder={this.props.titlePlaceholder}
-          disabled={!!this.props.disabled}
+          bidi={this.title}
+          placeholder={this.attrs.titlePlaceholder}
+          disabled={!!this.attrs.disabled}
           onkeydown={this.onkeydown.bind(this)}
         />
       </h3>
@@ -71,7 +71,7 @@ export default class DiscussionComposer extends ComposerBody {
       this.composer.editor.moveCursorTo(0);
     }
 
-    m.redraw.strategy('none');
+    e.redraw = false;
   }
 
   hasChanges() {
@@ -101,7 +101,7 @@ export default class DiscussionComposer extends ComposerBody {
       .then((discussion) => {
         this.composer.hide();
         app.discussions.refresh();
-        m.route(app.route.discussion(discussion));
+        m.route.set(app.route.discussion(discussion));
       }, this.loaded.bind(this));
   }
 }

js/src/forum/components/DiscussionHero.js

@@ -5,7 +5,7 @@ import listItems from '../../common/helpers/listItems';
 /**
  * The `DiscussionHero` component displays the hero on a discussion page.
  *
- * ### Props
+ * ### attrs
  *
  * - `discussion`
  */
@@ -27,7 +27,7 @@ export default class DiscussionHero extends Component {
    */
   items() {
     const items = new ItemList();
-    const discussion = this.props.discussion;
+    const discussion = this.attrs.discussion;
     const badges = discussion.badges().toArray();
 
     if (badges.length) {

js/src/forum/components/DiscussionList.js

@@ -7,17 +7,13 @@ import Placeholder from '../../common/components/Placeholder';
 /**
  * The `DiscussionList` component displays a list of discussions.
  *
- * ### Props
+ * ### Attrs
  *
  * - `state` A DiscussionListState object that represents the discussion lists's state.
  */
 export default class DiscussionList extends Component {
-  init() {
-    this.state = this.props.state;
-  }
-
   view() {
-    const state = this.state;
+    const state = this.attrs.state;
 
     const params = state.getParams();
     let loading;
@@ -25,11 +21,13 @@ export default class DiscussionList extends Component {
     if (state.isLoading()) {
       loading = LoadingIndicator.component();
     } else if (state.moreResults) {
-      loading = Button.component({
-        children: app.translator.trans('core.forum.discussion_list.load_more_button'),
-        className: 'Button',
-        onclick: state.loadMore.bind(state),
-      });
+      loading = Button.component(
+        {
+          className: 'Button',
+          onclick: state.loadMore.bind(state),
+        },
+        app.translator.trans('core.forum.discussion_list.load_more_button')
+      );
     }
 
     if (state.empty()) {

js/src/forum/components/DiscussionListItem.js

@@ -1,4 +1,5 @@
 import Component from '../../common/Component';
+import Link from '../../common/components/Link';
 import avatar from '../../common/helpers/avatar';
 import listItems from '../../common/helpers/listItems';
 import highlight from '../../common/helpers/highlight';
@@ -8,24 +9,26 @@ import ItemList from '../../common/utils/ItemList';
 import abbreviateNumber from '../../common/utils/abbreviateNumber';
 import Dropdown from '../../common/components/Dropdown';
 import TerminalPost from './TerminalPost';
-import PostPreview from './PostPreview';
 import SubtreeRetainer from '../../common/utils/SubtreeRetainer';
 import DiscussionControls from '../utils/DiscussionControls';
 import slidable from '../utils/slidable';
 import extractText from '../../common/utils/extractText';
 import classList from '../../common/utils/classList';
 
+import { escapeRegExp } from 'lodash-es';
 /**
  * The `DiscussionListItem` component shows a single discussion in the
  * discussion list.
  *
- * ### Props
+ * ### Attrs
  *
  * - `discussion`
  * - `params`
  */
 export default class DiscussionListItem extends Component {
-  init() {
+  oninit(vnode) {
+    super.oninit(vnode);
+
     /**
      * Set up a subtree retainer so that the discussion will not be redrawn
      * unless new data comes in.
@@ -33,7 +36,7 @@ export default class DiscussionListItem extends Component {
      * @type {SubtreeRetainer}
      */
     this.subtree = new SubtreeRetainer(
-      () => this.props.discussion.freshness,
+      () => this.attrs.discussion.freshness,
       () => {
         const time = app.session.user && app.session.user.markedAllAsReadAt();
         return time && time.getTime();
@@ -42,37 +45,34 @@ export default class DiscussionListItem extends Component {
     );
   }
 
-  attrs() {
+  elementAttrs() {
     return {
       className: classList([
         'DiscussionListItem',
         this.active() ? 'active' : '',
-        this.props.discussion.isHidden() ? 'DiscussionListItem--hidden' : '',
+        this.attrs.discussion.isHidden() ? 'DiscussionListItem--hidden' : '',
+        'ontouchstart' in window ? 'Slidable' : '',
       ]),
     };
   }
 
   view() {
-    const retain = this.subtree.retain();
-
-    if (retain) return retain;
-
-    const discussion = this.props.discussion;
+    const discussion = this.attrs.discussion;
     const user = discussion.user();
     const isUnread = discussion.isUnread();
     const isRead = discussion.isRead();
     const showUnread = !this.showRepliesCount() && isUnread;
     let jumpTo = 0;
     const controls = DiscussionControls.controls(discussion, this).toArray();
-    const attrs = this.attrs();
+    const attrs = this.elementAttrs();
 
-    if (this.props.params.q) {
+    if (this.attrs.params.q) {
       const post = discussion.mostRelevantPost();
       if (post) {
         jumpTo = post.number();
       }
 
-      const phrase = this.props.params.q;
+      const phrase = escapeRegExp(this.attrs.params.q);
       this.highlightRegExp = new RegExp(phrase + '|' + phrase.trim().replace(/\s+/g, '|'), 'gi');
     } else {
       jumpTo = Math.min(discussion.lastPostNumber(), (discussion.lastReadPostNumber() || 0) + 1);
@@ -81,42 +81,43 @@ export default class DiscussionListItem extends Component {
     return (
       <div {...attrs}>
         {controls.length
-          ? Dropdown.component({
-              icon: 'fas fa-ellipsis-v',
-              children: controls,
-              className: 'DiscussionListItem-controls',
-              buttonClassName: 'Button Button--icon Button--flat Slidable-underneath Slidable-underneath--right',
-            })
+          ? Dropdown.component(
+              {
+                icon: 'fas fa-ellipsis-v',
+                className: 'DiscussionListItem-controls',
+                buttonClassName: 'Button Button--icon Button--flat Slidable-underneath Slidable-underneath--right',
+              },
+              controls
+            )
           : ''}
 
-        <a
+        <span
           className={'Slidable-underneath Slidable-underneath--left Slidable-underneath--elastic' + (isUnread ? '' : ' disabled')}
           onclick={this.markAsRead.bind(this)}
         >
           {icon('fas fa-check')}
-        </a>
+        </span>
 
         <div className={'DiscussionListItem-content Slidable-content' + (isUnread ? ' unread' : '') + (isRead ? ' read' : '')}>
-          <a
+          <Link
             href={user ? app.route.user(user) : '#'}
             className="DiscussionListItem-author"
             title={extractText(
               app.translator.trans('core.forum.discussion_list.started_text', { user: user, ago: humanTime(discussion.createdAt()) })
             )}
-            config={function (element) {
-              $(element).tooltip({ placement: 'right' });
-              m.route.apply(this, arguments);
+            oncreate={function (vnode) {
+              $(vnode.dom).tooltip({ placement: 'right' });
             }}
           >
             {avatar(user, { title: '' })}
-          </a>
+          </Link>
 
           <ul className="DiscussionListItem-badges badges">{listItems(discussion.badges().toArray())}</ul>
 
-          <a href={app.route.discussion(discussion, jumpTo)} config={m.route} className="DiscussionListItem-main">
+          <Link href={app.route.discussion(discussion, jumpTo)} className="DiscussionListItem-main">
             <h3 className="DiscussionListItem-title">{highlight(discussion.title(), this.highlightRegExp)}</h3>
             <ul className="DiscussionListItem-info">{listItems(this.infoItems().toArray())}</ul>
-          </a>
+          </Link>
 
           <span
             className="DiscussionListItem-count"
@@ -130,19 +131,25 @@ export default class DiscussionListItem extends Component {
     );
   }
 
-  config(isInitialized) {
-    if (isInitialized) return;
+  oncreate(vnode) {
+    super.oncreate(vnode);
 
     // If we're on a touch device, set up the discussion row to be slidable.
     // This allows the user to drag the row to either side of the screen to
     // reveal controls.
     if ('ontouchstart' in window) {
-      const slidableInstance = slidable(this.$().addClass('Slidable'));
+      const slidableInstance = slidable(this.$());
 
       this.$('.DiscussionListItem-controls').on('hidden.bs.dropdown', () => slidableInstance.reset());
     }
   }
 
+  onbeforeupdate(vnode, old) {
+    super.onbeforeupdate(vnode, old);
+
+    return this.subtree.needsRebuild();
+  }
+
   /**
    * Determine whether or not the discussion is currently being viewed.
    *
@@ -151,7 +158,7 @@ export default class DiscussionListItem extends Component {
   active() {
     const idParam = m.route.param('id');
 
-    return idParam && idParam.split('-')[0] === this.props.discussion.id();
+    return idParam && idParam.split('-')[0] === this.attrs.discussion.id();
   }
 
   /**
@@ -162,7 +169,7 @@ export default class DiscussionListItem extends Component {
    * @return {Boolean}
    */
   showFirstPost() {
-    return ['newest', 'oldest'].indexOf(this.props.params.sort) !== -1;
+    return ['newest', 'oldest'].indexOf(this.attrs.params.sort) !== -1;
   }
 
   /**
@@ -172,14 +179,14 @@ export default class DiscussionListItem extends Component {
    * @return {Boolean}
    */
   showRepliesCount() {
-    return this.props.params.sort === 'replies';
+    return this.attrs.params.sort === 'replies';
   }
 
   /**
    * Mark the discussion as read.
    */
   markAsRead() {
-    const discussion = this.props.discussion;
+    const discussion = this.attrs.discussion;
 
     if (discussion.isUnread()) {
       discussion.save({ lastReadPostNumber: discussion.lastPostNumber() });
@@ -196,8 +203,8 @@ export default class DiscussionListItem extends Component {
   infoItems() {
     const items = new ItemList();
 
-    if (this.props.params.q) {
-      const post = this.props.discussion.mostRelevantPost() || this.props.discussion.firstPost();
+    if (this.attrs.params.q) {
+      const post = this.attrs.discussion.mostRelevantPost() || this.attrs.discussion.firstPost();
 
       if (post && post.contentType() === 'comment') {
         const excerpt = highlight(post.contentPlain(), this.highlightRegExp, 175);
@@ -207,7 +214,7 @@ export default class DiscussionListItem extends Component {
       items.add(
         'terminalPost',
         TerminalPost.component({
-          discussion: this.props.discussion,
+          discussion: this.attrs.discussion,
           lastPost: !this.showFirstPost(),
         })
       );

js/src/forum/components/DiscussionListPane.js

@@ -0,0 +1,67 @@
+import DiscussionList from './DiscussionList';
+import Component from '../../common/Component';
+
+const hotEdge = (e) => {
+  if (e.pageX < 10) app.pane.show();
+};
+
+/**
+ * The `DiscussionListPane` component displays the list of previously viewed
+ * discussions in a panel that can be displayed by moving the mouse to the left
+ * edge of the screen, where it can also be pinned in place.
+ *
+ * ### Attrs
+ *
+ * - `state` A DiscussionListState object that represents the discussion lists's state.
+ */
+export default class DiscussionListPane extends Component {
+  view() {
+    if (!this.attrs.state.hasDiscussions()) {
+      return;
+    }
+
+    return <div className="DiscussionPage-list">{this.enoughSpace() && <DiscussionList state={this.attrs.state} />}</div>;
+  }
+
+  oncreate(vnode) {
+    super.oncreate(vnode);
+
+    const $list = $(vnode.dom);
+
+    // When the mouse enters and leaves the discussions pane, we want to show
+    // and hide the pane respectively. We also create a 10px 'hot edge' on the
+    // left of the screen to activate the pane.
+    const pane = app.pane;
+    $list.hover(pane.show.bind(pane), pane.onmouseleave.bind(pane));
+
+    $(document).on('mousemove', hotEdge);
+
+    // If the discussion we are viewing is listed in the discussion list, then
+    // we will make sure it is visible in the viewport – if it is not we will
+    // scroll the list down to it.
+    const $discussion = $list.find('.DiscussionListItem.active');
+    if ($discussion.length) {
+      const listTop = $list.offset().top;
+      const listBottom = listTop + $list.outerHeight();
+      const discussionTop = $discussion.offset().top;
+      const discussionBottom = discussionTop + $discussion.outerHeight();
+
+      if (discussionTop < listTop || discussionBottom > listBottom) {
+        $list.scrollTop($list.scrollTop() - listTop + discussionTop);
+      }
+    }
+  }
+
+  onremove() {
+    $(document).off('mousemove', hotEdge);
+  }
+
+  /**
+   * Are we on a device that's larger than we consider "mobile"?
+   *
+   * @returns {boolean}
+   */
+  enoughSpace() {
+    return !$('.App-navigation').is(':visible');
+  }
+}

js/src/forum/components/DiscussionPage.js

@@ -1,21 +1,22 @@
 import Page from '../../common/components/Page';
 import ItemList from '../../common/utils/ItemList';
 import DiscussionHero from './DiscussionHero';
+import DiscussionListPane from './DiscussionListPane';
 import PostStream from './PostStream';
 import PostStreamScrubber from './PostStreamScrubber';
 import LoadingIndicator from '../../common/components/LoadingIndicator';
 import SplitDropdown from '../../common/components/SplitDropdown';
 import listItems from '../../common/helpers/listItems';
 import DiscussionControls from '../utils/DiscussionControls';
-import DiscussionList from './DiscussionList';
+import PostStreamState from '../states/PostStreamState';
 
 /**
  * The `DiscussionPage` component displays a whole discussion page, including
  * the discussion list pane, the hero, the posts, and the sidebar.
  */
 export default class DiscussionPage extends Page {
-  init() {
-    super.init();
+  oninit(vnode) {
+    super.oninit(vnode);
 
     /**
      * The discussion that is being viewed.
@@ -27,11 +28,11 @@ export default class DiscussionPage extends Page {
     /**
      * The number of the first post that is currently visible in the viewport.
      *
-     * @type {Integer}
+     * @type {number}
      */
-    this.near = null;
+    this.near = m.route.param('near') || 0;
 
-    this.refresh();
+    this.load();
 
     // If the discussion list has been loaded, then we'll enable the pane (and
     // hide it by default). Also, if we've just come from another discussion
@@ -41,10 +42,6 @@ export default class DiscussionPage extends Page {
     if (app.discussions.hasDiscussions()) {
       app.pane.enable();
       app.pane.hide();
-
-      if (app.previous.matches(DiscussionPage)) {
-        m.redraw.strategy('diff');
-      }
     }
 
     app.history.push('discussion');
@@ -52,27 +49,8 @@ export default class DiscussionPage extends Page {
     this.bodyClass = 'App--discussion';
   }
 
-  onunload(e) {
-    // If we have routed to the same discussion as we were viewing previously,
-    // cancel the unloading of this controller and instead prompt the post
-    // stream to jump to the new 'near' param.
-    if (this.discussion) {
-      const idParam = m.route.param('id');
-
-      if (idParam && idParam.split('-')[0] === this.discussion.id()) {
-        e.preventDefault();
-
-        const near = m.route.param('near') || '1';
-
-        if (near !== String(this.near)) {
-          this.stream.goToNumber(near);
-        }
-
-        this.near = null;
-        return;
-      }
-    }
-
+  onremove() {
+    super.onremove();
     // If we are indeed navigating away from this discussion, then disable the
     // discussion list pane. Also, if we're composing a reply to this
     // discussion, minimize the composer – unless it's empty, in which case
@@ -91,14 +69,7 @@ export default class DiscussionPage extends Page {
 
     return (
       <div className="DiscussionPage">
-        {app.discussions.hasDiscussions() ? (
-          <div className="DiscussionPage-list" config={this.configPane.bind(this)}>
-            {!$('.App-navigation').is(':visible') && <DiscussionList state={app.discussions} />}
-          </div>
-        ) : (
-          ''
-        )}
-
+        <DiscussionListPane state={app.discussions} />
         <div className="DiscussionPage-discussion">
           {discussion
             ? [
@@ -107,7 +78,13 @@ export default class DiscussionPage extends Page {
                   <nav className="DiscussionPage-nav">
                     <ul>{listItems(this.sidebarItems().toArray())}</ul>
                   </nav>
-                  <div className="DiscussionPage-stream">{this.stream.render()}</div>
+                  <div className="DiscussionPage-stream">
+                    {PostStream.component({
+                      discussion,
+                      stream: this.stream,
+                      onPositionChange: this.positionChanged.bind(this),
+                    })}
+                  </div>
                 </div>,
               ]
             : LoadingIndicator.component({ className: 'LoadingIndicator--block' })}
@@ -116,21 +93,10 @@ export default class DiscussionPage extends Page {
     );
   }
 
-  config(...args) {
-    super.config(...args);
-
-    if (this.discussion) {
-      app.setTitle(this.discussion.title());
-    }
-  }
-
   /**
-   * Clear and reload the discussion.
+   * Load the discussion from the API or use the preloaded one.
    */
-  refresh() {
-    this.near = m.route.param('near') || 0;
-    this.discussion = null;
-
+  load() {
     const preloadedDiscussion = app.preloadedApiDocument();
     if (preloadedDiscussion) {
       // We must wrap this in a setTimeout because if we are mounting this
@@ -144,7 +110,7 @@ export default class DiscussionPage extends Page {
       app.store.find('discussions', m.route.param('id').split('-')[0], params).then(this.show.bind(this));
     }
 
-    m.lazyRedraw();
+    m.redraw();
   }
 
   /**
@@ -165,9 +131,8 @@ export default class DiscussionPage extends Page {
    * @param {Discussion} discussion
    */
   show(discussion) {
-    this.discussion = discussion;
-
     app.history.push('discussion', discussion.title());
+    app.setTitle(discussion.title());
     app.setTitleCount(0);
 
     // When the API responds with a discussion, it will also include a number of
@@ -190,61 +155,20 @@ export default class DiscussionPage extends Page {
             record.relationships.discussion.data.id === discussionId
         )
         .map((record) => app.store.getById('posts', record.id))
-        .sort((a, b) => a.id() - b.id())
+        .sort((a, b) => a.createdAt() - b.createdAt())
         .slice(0, 20);
     }
 
     // Set up the post stream for this discussion, along with the first page of
     // posts we want to display. Tell the stream to scroll down and highlight
     // the specific post that was routed to.
-    this.stream = new PostStream({ discussion, includedPosts });
-    this.stream.on('positionChanged', this.positionChanged.bind(this));
-    this.stream.goToNumber(m.route.param('near') || (includedPosts[0] && includedPosts[0].number()), true);
+    this.stream = new PostStreamState(discussion, includedPosts);
+    this.stream.goToNumber(m.route.param('near') || (includedPosts[0] && includedPosts[0].number()), true).then(() => {
+      this.discussion = discussion;
 
-    app.current.set('discussion', discussion);
-    app.current.set('stream', this.stream);
-  }
-
-  /**
-   * Configure the discussion list pane.
-   *
-   * @param {DOMElement} element
-   * @param {Boolean} isInitialized
-   * @param {Object} context
-   */
-  configPane(element, isInitialized, context) {
-    if (isInitialized) return;
-
-    context.retain = true;
-
-    const $list = $(element);
-
-    // When the mouse enters and leaves the discussions pane, we want to show
-    // and hide the pane respectively. We also create a 10px 'hot edge' on the
-    // left of the screen to activate the pane.
-    const pane = app.pane;
-    $list.hover(pane.show.bind(pane), pane.onmouseleave.bind(pane));
-
-    const hotEdge = (e) => {
-      if (e.pageX < 10) pane.show();
-    };
-    $(document).on('mousemove', hotEdge);
-    context.onunload = () => $(document).off('mousemove', hotEdge);
-
-    // If the discussion we are viewing is listed in the discussion list, then
-    // we will make sure it is visible in the viewport – if it is not we will
-    // scroll the list down to it.
-    const $discussion = $list.find('.DiscussionListItem.active');
-    if ($discussion.length) {
-      const listTop = $list.offset().top;
-      const listBottom = listTop + $list.outerHeight();
-      const discussionTop = $discussion.offset().top;
-      const discussionBottom = discussionTop + $discussion.outerHeight();
-
-      if (discussionTop < listTop || discussionBottom > listBottom) {
-        $list.scrollTop($list.scrollTop() - listTop + discussionTop);
-      }
-    }
+      app.current.set('discussion', discussion);
+      app.current.set('stream', this.stream);
+    });
   }
 
   /**
@@ -257,12 +181,14 @@ export default class DiscussionPage extends Page {
 
     items.add(
       'controls',
-      SplitDropdown.component({
-        children: DiscussionControls.controls(this.discussion, this).toArray(),
-        icon: 'fas fa-ellipsis-v',
-        className: 'App-primaryControl',
-        buttonClassName: 'Button--primary',
-      })
+      SplitDropdown.component(
+        {
+          icon: 'fas fa-ellipsis-v',
+          className: 'App-primaryControl',
+          buttonClassName: 'Button--primary',
+        },
+        DiscussionControls.controls(this.discussion, this).toArray()
+      )
     );
 
     items.add(
@@ -291,9 +217,7 @@ export default class DiscussionPage extends Page {
     // replace it into the window's history and our own history stack.
     const url = app.route.discussion(discussion, (this.near = startNumber));
 
-    m.route(url, true);
     window.history.replaceState(null, document.title, url);
-
     app.history.push('discussion', discussion.title());
 
     // If the user hasn't read past here before, then we'll update their read

js/src/forum/components/DiscussionRenamedNotification.js

@@ -4,9 +4,9 @@ import Notification from './Notification';
  * The `DiscussionRenamedNotification` component displays a notification which
  * indicates that a discussion has had its title changed.
  *
- * ### Props
+ * ### Attrs
  *
- * - All of the props for Notification
+ * - All of the attrs for Notification
  */
 export default class DiscussionRenamedNotification extends Notification {
   icon() {
@@ -14,12 +14,12 @@ export default class DiscussionRenamedNotification extends Notification {
   }
 
   href() {
-    const notification = this.props.notification;
+    const notification = this.attrs.notification;
 
     return app.route.discussion(notification.subject(), notification.content().postNumber);
   }
 
   content() {
-    return app.translator.trans('core.forum.notifications.discussion_renamed_text', { user: this.props.notification.fromUser() });
+    return app.translator.trans('core.forum.notifications.discussion_renamed_text', { user: this.attrs.notification.fromUser() });
   }
 }

js/src/forum/components/DiscussionRenamedPost.js

@@ -5,9 +5,9 @@ import extractText from '../../common/utils/extractText';
  * The `DiscussionRenamedPost` component displays a discussion event post
  * indicating that the discussion has been renamed.
  *
- * ### Props
+ * ### Attrs
  *
- * - All of the props for EventPost
+ * - All of the attrs for EventPost
  */
 export default class DiscussionRenamedPost extends EventPost {
   icon() {
@@ -22,7 +22,7 @@ export default class DiscussionRenamedPost extends EventPost {
   }
 
   descriptionData() {
-    const post = this.props.post;
+    const post = this.attrs.post;
     const oldTitle = post.content()[0];
     const newTitle = post.content()[1];
 

js/src/forum/components/DiscussionsSearchSource.js

@@ -1,5 +1,6 @@
 import highlight from '../../common/helpers/highlight';
 import LinkButton from '../../common/components/LinkButton';
+import Link from '../../common/components/Link';
 
 /**
  * The `DiscussionsSearchSource` finds and displays discussion search results in
@@ -34,21 +35,23 @@ export default class DiscussionsSearchSource {
     return [
       <li className="Dropdown-header">{app.translator.trans('core.forum.search.discussions_heading')}</li>,
       <li>
-        {LinkButton.component({
-          icon: 'fas fa-search',
-          children: app.translator.trans('core.forum.search.all_discussions_button', { query }),
-          href: app.route('index', { q: query }),
-        })}
+        {LinkButton.component(
+          {
+            icon: 'fas fa-search',
+            href: app.route('index', { q: query }),
+          },
+          app.translator.trans('core.forum.search.all_discussions_button', { query })
+        )}
       </li>,
       results.map((discussion) => {
         const mostRelevantPost = discussion.mostRelevantPost();
 
         return (
           <li className="DiscussionSearchResult" data-index={'discussions' + discussion.id()}>
-            <a href={app.route.discussion(discussion, mostRelevantPost && mostRelevantPost.number())} config={m.route}>
+            <Link href={app.route.discussion(discussion, mostRelevantPost && mostRelevantPost.number())}>
               <div className="DiscussionSearchResult-title">{highlight(discussion.title(), query)}</div>
               {mostRelevantPost ? <div className="DiscussionSearchResult-excerpt">{highlight(mostRelevantPost.contentPlain(), query, 100)}</div> : ''}
-            </a>
+            </Link>
           </li>
         );
       }),