Merge commit '9b0050e9aabe4be65c78ccf292a348f309d50ccd' as 'docs'

```
git subtree add --prefix=docs/ https://github.com/gohugoio/hugoDocs.git master --squash
```

Closes #11925

docs/content/en/content-management/syntax-highlighting.md

@@ -0,0 +1,138 @@
+---
+title: Syntax highlighting
+description: Hugo comes with really fast syntax highlighting from Chroma.
+categories: [content management]
+keywords: [highlighting,chroma,code blocks,syntax]
+menu:
+  docs:
+    parent: content-management
+    weight: 240
+weight: 240
+toc: true
+aliases: [/extras/highlighting/,/extras/highlight/,/tools/syntax-highlighting/]
+---
+
+Hugo uses [Chroma](https://github.com/alecthomas/chroma) as its code highlighter; it is built in Go and is really, really fast.
+
+## Configure syntax highlighter
+
+See [Configure Highlight](/getting-started/configuration-markup#highlight).
+
+## Generate syntax highlighter CSS
+
+If you run with `markup.highlight.noClasses=false` in your site configuration, you need a style sheet.
+
+You can generate one with Hugo:
+
+```sh
+hugo gen chromastyles --style=monokai > syntax.css
+```
+
+Run `hugo gen chromastyles -h` for more options. See https://xyproto.github.io/splash/docs/ for a gallery of available styles.
+
+## Highlight shortcode
+
+Highlighting is carried out via the built-in [`highlight` shortcode](/content-management/shortcodes/#highlight). It takes exactly one required parameter for the programming language to be highlighted and requires a closing shortcode.
+
+Options:
+
+* `linenos`: configure line numbers. Valid values are `true`, `false`, `table`, or `inline`. `false` will turn off line numbers if it's configured to be on in site configuration. `table` will give copy-and-paste friendly code blocks.
+* `hl_lines`: lists a set of line numbers or line number ranges to be highlighted.
+* `linenostart=199`: starts the line number count from 199.
+* `anchorlinenos`: Configure anchors on line numbers. Valid values are `true` or `false`;
+* `lineanchors`: Configure a prefix for the anchors on line numbers. Will be suffixed with `-`, so linking to the line number 1 with the option `lineanchors=prefix` adds the anchor `prefix-1` to the page.  
+* `hl_inline`  Highlight inside a `<code>` (inline HTML element) tag. Valid values are `true` or `false`. The `code` tag will get a class with name `code-inline`. {{< new-in 0.101.0 >}}
+
+### Example: highlight shortcode
+
+```go-html-template
+{{</* highlight go "linenos=table,hl_lines=8 15-17,linenostart=199" */>}}
+// ... code
+{{</* / highlight */>}}
+```
+
+Gives this:
+
+{{< highlight go "linenos=table,hl_lines=8 15-17,linenostart=199" >}}
+// GetTitleFunc returns a func that can be used to transform a string to
+// title case.
+//
+// The supported styles are
+//
+// - "Go" (strings.Title)
+// - "AP" (see https://www.apstylebook.com/)
+// - "Chicago" (see https://www.chicagomanualofstyle.org/home.html)
+//
+// If an unknown or empty style is provided, AP style is what you get.
+func GetTitleFunc(style string) func(s string) string {
+  switch strings.ToLower(style) {
+  case "go":
+    return strings.Title
+  case "chicago":
+    return transform.NewTitleConverter(transform.ChicagoStyle)
+  default:
+    return transform.NewTitleConverter(transform.APStyle)
+  }
+}
+{{< / highlight >}}
+
+## Highlight Hugo/Go template code
+
+For highlighting Hugo/Go template code on your page, add `/*` after the opening double curly braces and `*/` before closing curly braces.
+
+``` go
+{{</*/* myshortcode */*/>}}
+```
+
+Gives this:
+
+``` go
+{{</* myshortcode */>}}
+```
+
+## Highlight template function
+
+See [Highlight](/functions/transform/highlight/).
+
+## Highlighting in code fences
+
+Highlighting in code fences is enabled by default.
+
+````txt
+```go {linenos=table,hl_lines=[8,"15-17"],linenostart=199}
+// ... code
+```
+````
+
+Gives this:
+
+```go {linenos=table,hl_lines=[8,"15-17"],linenostart=199}
+// GetTitleFunc returns a func that can be used to transform a string to
+// title case.
+//
+// The supported styles are
+//
+// - "Go" (strings.Title)
+// - "AP" (see https://www.apstylebook.com/)
+// - "Chicago" (see https://www.chicagomanualofstyle.org/home.html)
+//
+// If an unknown or empty style is provided, AP style is what you get.
+func GetTitleFunc(style string) func(s string) string {
+  switch strings.ToLower(style) {
+  case "go":
+    return strings.Title
+  case "chicago":
+    return transform.NewTitleConverter(transform.ChicagoStyle)
+  default:
+    return transform.NewTitleConverter(transform.APStyle)
+  }
+}
+```
+
+The options are the same as in the [highlighting shortcode](/content-management/syntax-highlighting/#highlight-shortcode), including `linenos=false`, but note the slightly different Markdown attribute syntax.
+
+## List of Chroma highlighting languages
+
+The full list of Chroma lexers and their aliases (which is the identifier used in the `highlight` template func or when doing highlighting in code fences):
+
+{{< chroma-lexers >}}