diff --git a/docs/.htmllintrc b/docs/.htmllintrc
index e15284536e..d88560faa9 100644
--- a/docs/.htmllintrc
+++ b/docs/.htmllintrc
@@ -9,6 +9,7 @@
   "html-valid-content-model": false,
   "id-class-ignore-regex": "(onclick|content|[a-z]+([A-Z][a-z])+)",
   "id-class-style": "dash",
+  "img-req-src": false,
   "img-req-alt": false,
   "indent-style": "spaces",
   "indent-width": 2,
diff --git a/docs/components/carousel.md b/docs/components/carousel.md
index ab84bf460d..af00dc526c 100644
--- a/docs/components/carousel.md
+++ b/docs/components/carousel.md
@@ -186,45 +186,45 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 100px;">Name</th>
-     <th style="width: 50px;">Type</th>
-     <th style="width: 50px;">Default</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 100px;">Name</th>
+      <th style="width: 50px;">Type</th>
+      <th style="width: 50px;">Default</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
-   <tr>
-     <td>interval</td>
-     <td>number</td>
-     <td>5000</td>
-     <td>The amount of time to delay between automatically cycling an item. If false, carousel will not automatically cycle.</td>
-   </tr>
-   <tr>
-     <td>keyboard</td>
-     <td>boolean</td>
-     <td>true</td>
-     <td>Whether the carousel should react to keyboard events.</td>
-   </tr>
-   <tr>
-     <td>pause</td>
-     <td>string | boolean</td>
-     <td>"hover"</td>
-     <td><p>If set to <code>"hover"</code>, pauses the cycling of the carousel on <code>mouseenter</code> and resumes the cycling of the carousel on <code>mouseleave</code>. If set to <code>false</code>, hovering over the carousel won't pause it.</p>
-     <p>On touch-enabled devices, when set to <code>"hover"</code>, cycling will pause on <code>touchend</code> (once the user finished interacting with the carousel) for two intervals, before automatically resuming. Note that this is in addition to the above mouse behavior.</p></td>
-   </tr>
-   <tr>
-     <td>ride</td>
-     <td>string</td>
-     <td>false</td>
-     <td>Autoplays the carousel after the user manually cycles the first item. If "carousel", autoplays the carousel on load.</td>
-   </tr>
-   <tr>
-     <td>wrap</td>
-     <td>boolean</td>
-     <td>true</td>
-     <td>Whether the carousel should cycle continuously or have hard stops.</td>
-   </tr>
+    <tr>
+      <td>interval</td>
+      <td>number</td>
+      <td>5000</td>
+      <td>The amount of time to delay between automatically cycling an item. If false, carousel will not automatically cycle.</td>
+    </tr>
+    <tr>
+      <td>keyboard</td>
+      <td>boolean</td>
+      <td>true</td>
+      <td>Whether the carousel should react to keyboard events.</td>
+    </tr>
+    <tr>
+      <td>pause</td>
+      <td>string | boolean</td>
+      <td>"hover"</td>
+      <td><p>If set to <code>"hover"</code>, pauses the cycling of the carousel on <code>mouseenter</code> and resumes the cycling of the carousel on <code>mouseleave</code>. If set to <code>false</code>, hovering over the carousel won't pause it.</p>
+      <p>On touch-enabled devices, when set to <code>"hover"</code>, cycling will pause on <code>touchend</code> (once the user finished interacting with the carousel) for two intervals, before automatically resuming. Note that this is in addition to the above mouse behavior.</p></td>
+    </tr>
+    <tr>
+      <td>ride</td>
+      <td>string</td>
+      <td>false</td>
+      <td>Autoplays the carousel after the user manually cycles the first item. If "carousel", autoplays the carousel on load.</td>
+    </tr>
+    <tr>
+      <td>wrap</td>
+      <td>boolean</td>
+      <td>true</td>
+      <td>Whether the carousel should cycle continuously or have hard stops.</td>
+    </tr>
   </tbody>
 </table>
 
@@ -276,20 +276,20 @@ All carousel events are fired at the carousel itself (i.e. at the `<div class="c
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 150px;">Event Type</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 150px;">Event Type</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
-   <tr>
-     <td>slide.bs.carousel</td>
-     <td>This event fires immediately when the <code>slide</code> instance method is invoked.</td>
-   </tr>
-   <tr>
-     <td>slid.bs.carousel</td>
-     <td>This event is fired when the carousel has completed its slide transition.</td>
-   </tr>
+    <tr>
+      <td>slide.bs.carousel</td>
+      <td>This event fires immediately when the <code>slide</code> instance method is invoked.</td>
+    </tr>
+    <tr>
+      <td>slid.bs.carousel</td>
+      <td>This event is fired when the carousel has completed its slide transition.</td>
+    </tr>
   </tbody>
 </table>
 
diff --git a/docs/components/collapse.md b/docs/components/collapse.md
index a86678ad18..65b8171bdc 100644
--- a/docs/components/collapse.md
+++ b/docs/components/collapse.md
@@ -153,26 +153,26 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 100px;">Name</th>
-     <th style="width: 50px;">Type</th>
-     <th style="width: 50px;">Default</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 100px;">Name</th>
+      <th style="width: 50px;">Type</th>
+      <th style="width: 50px;">Default</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
-   <tr>
-     <td>parent</td>
-     <td>selector</td>
-     <td>false</td>
-     <td>If a selector is provided, then all collapsible elements under the specified parent will be closed when this collapsible item is shown. (similar to traditional accordion behavior - this is dependent on the <code>card</code> class). The attribute has to be set on the target collapsible area.</td>
-   </tr>
-   <tr>
-     <td>toggle</td>
-     <td>boolean</td>
-     <td>true</td>
-     <td>Toggles the collapsible element on invocation</td>
-   </tr>
+    <tr>
+      <td>parent</td>
+      <td>selector</td>
+      <td>false</td>
+      <td>If a selector is provided, then all collapsible elements under the specified parent will be closed when this collapsible item is shown. (similar to traditional accordion behavior - this is dependent on the <code>card</code> class). The attribute has to be set on the target collapsible area.</td>
+    </tr>
+    <tr>
+      <td>toggle</td>
+      <td>boolean</td>
+      <td>true</td>
+      <td>Toggles the collapsible element on invocation</td>
+    </tr>
   </tbody>
 </table>
 
@@ -209,30 +209,28 @@ Bootstrap's collapse class exposes a few events for hooking into collapse functi
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 150px;">Event Type</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 150px;">Event Type</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
-   <tr>
-     <td>show.bs.collapse</td>
-     <td>This event fires immediately when the <code>show</code> instance method is called.</td>
-   </tr>
-   <tr>
-     <td>shown.bs.collapse</td>
-     <td>This event is fired when a collapse element has been made visible to the user (will wait for CSS transitions to complete).</td>
-   </tr>
-   <tr>
-     <td>hide.bs.collapse</td>
-     <td>
-      This event is fired immediately when the <code>hide</code> method has been called.
-     </td>
-   </tr>
-   <tr>
-     <td>hidden.bs.collapse</td>
-     <td>This event is fired when a collapse element has been hidden from the user (will wait for CSS transitions to complete).</td>
-   </tr>
+    <tr>
+      <td>show.bs.collapse</td>
+      <td>This event fires immediately when the <code>show</code> instance method is called.</td>
+    </tr>
+    <tr>
+      <td>shown.bs.collapse</td>
+      <td>This event is fired when a collapse element has been made visible to the user (will wait for CSS transitions to complete).</td>
+    </tr>
+    <tr>
+      <td>hide.bs.collapse</td>
+      <td>This event is fired immediately when the <code>hide</code> method has been called.</td>
+    </tr>
+    <tr>
+      <td>hidden.bs.collapse</td>
+      <td>This event is fired when a collapse element has been hidden from the user (will wait for CSS transitions to complete).</td>
+    </tr>
   </tbody>
 </table>
 
diff --git a/docs/components/forms.md b/docs/components/forms.md
index 44cb1ed0df..52230fa54e 100644
--- a/docs/components/forms.md
+++ b/docs/components/forms.md
@@ -376,7 +376,7 @@ Be sure to add `.col-form-label` to your `<label>`s as well so they're verticall
       </div>
     </fieldset>
     <div class="form-group row">
-      <label class="col-sm-2">Checkbox</label>
+      <div class="col-sm-2">Checkbox</div>
       <div class="col-sm-10">
         <div class="form-check">
           <label class="form-check-label">
@@ -569,14 +569,14 @@ Should you have no text within the `<label>`, the input is positioned as you'd e
 
 ## Static controls
 
-When you need to place plain text next to a form label within a form, use the `.form-control-static` class on an element of your choice.
+If you want to have read-only fields in your form styled as plain text, use the `.form-control-static` class to remove the default form field styling and preserve the correct margin and padding.
 
 {% example html %}
 <form>
   <div class="form-group row">
-    <label class="col-sm-2 col-form-label">Email</label>
+    <label for="staticEmail" class="col-sm-2 col-form-label">Email</label>
     <div class="col-sm-10">
-      <p class="form-control-static">email@example.com</p>
+      <input type="text" readonly class="form-control-static" id="staticEmail" value="email@example.com">
     </div>
   </div>
   <div class="form-group row">
@@ -591,8 +591,8 @@ When you need to place plain text next to a form label within a form, use the `.
 {% example html %}
 <form class="form-inline">
   <div class="form-group">
-    <label class="sr-only">Email</label>
-    <p class="form-control-static">email@example.com</p>
+    <label for="staticEmail2" class="sr-only">Email</label>
+    <input type="text" readonly class="form-control-static" id="staticEmail2" value="email@example.com">
   </div>
   <div class="form-group mx-sm-3">
     <label for="inputPassword2" class="sr-only">Password</label>
@@ -604,7 +604,7 @@ When you need to place plain text next to a form label within a form, use the `.
 
 ## Disabled states
 
-Add the `disabled` boolean attribute on an input to prevent user interactions. Disabled inputs appear lighter and add a `not-allowed` cursor.
+Add the `disabled` boolean attribute on an input to prevent user interactions and make it appear lighter.
 
 {% highlight html %}
 <input class="form-control" id="disabledInput" type="text" placeholder="Disabled input here..." disabled>
diff --git a/docs/components/list-group.md b/docs/components/list-group.md
index fcaa364fb2..dcf605aeeb 100644
--- a/docs/components/list-group.md
+++ b/docs/components/list-group.md
@@ -328,17 +328,17 @@ If no tab was already active, the `hide.bs.tab` and `hidden.bs.tab` events will
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 150px;">Event type</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 150px;">Event type</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
     <tr>
       <td>show.bs.tab</td>
       <td>This event fires on tab show, but before the new tab has been shown. Use <code>event.target</code> and <code>event.relatedTarget</code> to target the active tab and the previous active tab (if available) respectively.</td>
-   </tr>
-   <tr>
+    </tr>
+    <tr>
       <td>shown.bs.tab</td>
       <td>This event fires on tab show after a tab has been shown. Use <code>event.target</code> and <code>event.relatedTarget</code> to target the active tab and the previous active tab (if available) respectively.</td>
     </tr>
diff --git a/docs/components/modal.md b/docs/components/modal.md
index 19254b8808..a2f4471d3c 100644
--- a/docs/components/modal.md
+++ b/docs/components/modal.md
@@ -510,38 +510,38 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 100px;">Name</th>
-     <th style="width: 50px;">Type</th>
-     <th style="width: 50px;">Default</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 100px;">Name</th>
+      <th style="width: 50px;">Type</th>
+      <th style="width: 50px;">Default</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
-   <tr>
-     <td>backdrop</td>
-     <td>boolean or the string <code>'static'</code></td>
-     <td>true</td>
-     <td>Includes a modal-backdrop element. Alternatively, specify <code>static</code> for a backdrop which doesn't close the modal on click.</td>
-   </tr>
-   <tr>
-     <td>keyboard</td>
-     <td>boolean</td>
-     <td>true</td>
-     <td>Closes the modal when escape key is pressed</td>
-   </tr>
-   <tr>
-     <td>focus</td>
-     <td>boolean</td>
-     <td>true</td>
-     <td>Puts the focus on the modal when initialized.</td>
-   </tr>
-   <tr>
-     <td>show</td>
-     <td>boolean</td>
-     <td>true</td>
-     <td>Shows the modal when initialized.</td>
-   </tr>
+    <tr>
+      <td>backdrop</td>
+      <td>boolean or the string <code>'static'</code></td>
+      <td>true</td>
+      <td>Includes a modal-backdrop element. Alternatively, specify <code>static</code> for a backdrop which doesn't close the modal on click.</td>
+    </tr>
+    <tr>
+      <td>keyboard</td>
+      <td>boolean</td>
+      <td>true</td>
+      <td>Closes the modal when escape key is pressed</td>
+    </tr>
+    <tr>
+      <td>focus</td>
+      <td>boolean</td>
+      <td>true</td>
+      <td>Puts the focus on the modal when initialized.</td>
+    </tr>
+    <tr>
+      <td>show</td>
+      <td>boolean</td>
+      <td>true</td>
+      <td>Shows the modal when initialized.</td>
+    </tr>
   </tbody>
 </table>
 
@@ -590,28 +590,28 @@ Bootstrap's modal class exposes a few events for hooking into modal functionalit
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 150px;">Event Type</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 150px;">Event Type</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
-   <tr>
-     <td>show.bs.modal</td>
-     <td>This event fires immediately when the <code>show</code> instance method is called. If caused by a click, the clicked element is available as the <code>relatedTarget</code> property of the event.</td>
-   </tr>
-   <tr>
-     <td>shown.bs.modal</td>
-     <td>This event is fired when the modal has been made visible to the user (will wait for CSS transitions to complete). If caused by a click, the clicked element is available as the <code>relatedTarget</code> property of the event.</td>
-   </tr>
-   <tr>
-     <td>hide.bs.modal</td>
-     <td>This event is fired immediately when the <code>hide</code> instance method has been called.</td>
-   </tr>
-   <tr>
-     <td>hidden.bs.modal</td>
-     <td>This event is fired when the modal has finished being hidden from the user (will wait for CSS transitions to complete).</td>
-   </tr>
+    <tr>
+      <td>show.bs.modal</td>
+      <td>This event fires immediately when the <code>show</code> instance method is called. If caused by a click, the clicked element is available as the <code>relatedTarget</code> property of the event.</td>
+    </tr>
+    <tr>
+      <td>shown.bs.modal</td>
+      <td>This event is fired when the modal has been made visible to the user (will wait for CSS transitions to complete). If caused by a click, the clicked element is available as the <code>relatedTarget</code> property of the event.</td>
+    </tr>
+    <tr>
+      <td>hide.bs.modal</td>
+      <td>This event is fired immediately when the <code>hide</code> instance method has been called.</td>
+    </tr>
+    <tr>
+      <td>hidden.bs.modal</td>
+      <td>This event is fired when the modal has finished being hidden from the user (will wait for CSS transitions to complete).</td>
+    </tr>
   </tbody>
 </table>
 
diff --git a/docs/components/navs.md b/docs/components/navs.md
index 9ab2535ed6..e929062291 100644
--- a/docs/components/navs.md
+++ b/docs/components/navs.md
@@ -636,17 +636,17 @@ If no tab was already active, then the `hide.bs.tab` and `hidden.bs.tab` events
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 150px;">Event Type</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 150px;">Event Type</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
     <tr>
       <td>show.bs.tab</td>
       <td>This event fires on tab show, but before the new tab has been shown. Use <code>event.target</code> and <code>event.relatedTarget</code> to target the active tab and the previous active tab (if available) respectively.</td>
-   </tr>
-   <tr>
+    </tr>
+    <tr>
       <td>shown.bs.tab</td>
       <td>This event fires on tab show after a tab has been shown. Use <code>event.target</code> and <code>event.relatedTarget</code> to target the active tab and the previous active tab (if available) respectively.</td>
     </tr>
diff --git a/docs/components/popovers.md b/docs/components/popovers.md
index cc1b0fe2e8..307b4cb6d6 100644
--- a/docs/components/popovers.md
+++ b/docs/components/popovers.md
@@ -201,9 +201,9 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
       <td>number | object</td>
       <td>0</td>
       <td>
-       <p>Delay showing and hiding the popover (ms) - does not apply to manual trigger type</p>
-       <p>If a number is supplied, delay is applied to both hide/show</p>
-       <p>Object structure is: <code>delay: { "show": 500, "hide": 100 }</code></p>
+        <p>Delay showing and hiding the popover (ms) - does not apply to manual trigger type</p>
+        <p>If a number is supplied, delay is applied to both hide/show</p>
+        <p>Object structure is: <code>delay: { "show": 500, "hide": 100 }</code></p>
       </td>
     </tr>
     <tr>
@@ -331,10 +331,10 @@ Toggles the ability for an element's popover to be shown or hidden.
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
+    <tr>
       <th style="width: 150px;">Event Type</th>
       <th>Description</th>
-   </tr>
+    </tr>
   </thead>
   <tbody>
     <tr>
diff --git a/docs/components/scrollspy.md b/docs/components/scrollspy.md
index ecabd51c54..80c0571618 100644
--- a/docs/components/scrollspy.md
+++ b/docs/components/scrollspy.md
@@ -292,20 +292,20 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 100px;">Name</th>
-     <th style="width: 100px;">Type</th>
-     <th style="width: 50px;">Default</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 100px;">Name</th>
+      <th style="width: 100px;">Type</th>
+      <th style="width: 50px;">Default</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
-   <tr>
-     <td>offset</td>
-     <td>number</td>
-     <td>10</td>
-     <td>Pixels to offset from top when calculating position of scroll.</td>
-   </tr>
+    <tr>
+      <td>offset</td>
+      <td>number</td>
+      <td>10</td>
+      <td>Pixels to offset from top when calculating position of scroll.</td>
+    </tr>
   </tbody>
 </table>
 
@@ -313,16 +313,16 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
 
 <table class="table table-bordered table-striped table-responsive">
   <thead>
-   <tr>
-     <th style="width: 150px;">Event Type</th>
-     <th>Description</th>
-   </tr>
+    <tr>
+      <th style="width: 150px;">Event Type</th>
+      <th>Description</th>
+    </tr>
   </thead>
   <tbody>
-   <tr>
-     <td>activate.bs.scrollspy</td>
-     <td>This event fires whenever a new item becomes activated by the scrollspy.</td>
-  </tr>
+    <tr>
+      <td>activate.bs.scrollspy</td>
+      <td>This event fires whenever a new item becomes activated by the scrollspy.</td>
+    </tr>
   </tbody>
 </table>
 
diff --git a/docs/components/tooltips.md b/docs/components/tooltips.md
index 7c7f9af8b0..55de9a886a 100644
--- a/docs/components/tooltips.md
+++ b/docs/components/tooltips.md
@@ -168,16 +168,16 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
       <td>false</td>
       <td>
         <p>Appends the tooltip to a specific element. Example: <code>container: 'body'</code>. This option is particularly useful in that it allows you to position the tooltip in the flow of the document near the triggering element - which will prevent the tooltip from floating away from the triggering element during a window resize.</p>
-     </td>
+      </td>
     </tr>
     <tr>
       <td>delay</td>
       <td>number | object</td>
       <td>0</td>
       <td>
-       <p>Delay showing and hiding the tooltip (ms) - does not apply to manual trigger type</p>
-       <p>If a number is supplied, delay is applied to both hide/show</p>
-       <p>Object structure is: <code>delay: { "show": 500, "hide": 100 }</code></p>
+        <p>Delay showing and hiding the tooltip (ms) - does not apply to manual trigger type</p>
+        <p>If a number is supplied, delay is applied to both hide/show</p>
+        <p>Object structure is: <code>delay: { "show": 500, "hide": 100 }</code></p>
       </td>
     </tr>
     <tr>
diff --git a/docs/examples/jumbotron/index.html b/docs/examples/jumbotron/index.html
index 8ac227e23f..35c308d14f 100644
--- a/docs/examples/jumbotron/index.html
+++ b/docs/examples/jumbotron/index.html
@@ -72,7 +72,7 @@
           <h2>Heading</h2>
           <p>Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui. </p>
           <p><a class="btn btn-secondary" href="#" role="button">View details &raquo;</a></p>
-       </div>
+        </div>
         <div class="col-md-4">
           <h2>Heading</h2>
           <p>Donec sed odio dui. Cras justo odio, dapibus ac facilisis in, egestas eget quam. Vestibulum id ligula porta felis euismod semper. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus.</p>
diff --git a/docs/examples/justified-nav/index.html b/docs/examples/justified-nav/index.html
index 0fcbf08564..23615bd605 100644
--- a/docs/examples/justified-nav/index.html
+++ b/docs/examples/justified-nav/index.html
@@ -75,7 +75,7 @@
           <h2>Heading</h2>
           <p>Donec id elit non mi porta gravida at eget metus. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa justo sit amet risus. Etiam porta sem malesuada magna mollis euismod. Donec sed odio dui. </p>
           <p><a class="btn btn-primary" href="#" role="button">View details &raquo;</a></p>
-       </div>
+        </div>
         <div class="col-lg-4">
           <h2>Heading</h2>
           <p>Donec sed odio dui. Cras justo odio, dapibus ac facilisis in, egestas eget quam. Vestibulum id ligula porta felis euismod semper. Fusce dapibus, tellus ac cursus commodo, tortor mauris condimentum nibh, ut fermentum massa.</p>
diff --git a/docs/getting-started/introduction.md b/docs/getting-started/introduction.md
index d70a42627c..0ca845a8a5 100644
--- a/docs/getting-started/introduction.md
+++ b/docs/getting-started/introduction.md
@@ -96,9 +96,7 @@ On the rare occasion you need to override it, use something like the following:
 
 {% highlight scss %}
 .selector-for-some-widget {
-  -webkit-box-sizing: content-box;
-     -moz-box-sizing: content-box;
-          box-sizing: content-box;
+  box-sizing: content-box;
 }
 {% endhighlight %}