Replace master with v3-dev after the branch switch. (#28287)

docs/_includes/getting-started/browser-device-support.html

@@ -124,11 +124,11 @@
   <h2 id="support-ie8-respondjs">Internet Explorer 8 and Respond.js</h2>
   <p>Beware of the following caveats when using Respond.js in your development and production environments for Internet Explorer 8.</p>
   <h3 id="respond-js-x-domain">Respond.js and cross-domain CSS</h3>
-  <p>Using Respond.js with CSS hosted on a different (sub)domain (for example, on a CDN) requires some additional setup. <a href="https://github.com/scottjehl/Respond/blob/master/README.md#cdnx-domain-setup">See the Respond.js docs</a> for details.</p>
+  <p>Using Respond.js with CSS hosted on a different (sub)domain (for example, on a CDN) requires some additional setup. <a href="https://github.com/scottjehl/Respond/blob/v3-dev/README.md#cdnx-domain-setup">See the Respond.js docs</a> for details.</p>
   <h3 id="respond-file-proto">Respond.js and <code>file://</code></h3>
-  <p>Due to browser security rules, Respond.js doesn't work with pages viewed via the <code>file://</code> protocol (like when opening a local HTML file). To test responsive features in IE8, view your pages over HTTP(S). <a href="https://github.com/scottjehl/Respond/blob/master/README.md#support--caveats">See the Respond.js docs</a> for details.</p>
+  <p>Due to browser security rules, Respond.js doesn't work with pages viewed via the <code>file://</code> protocol (like when opening a local HTML file). To test responsive features in IE8, view your pages over HTTP(S). <a href="https://github.com/scottjehl/Respond/blob/v3-dev/README.md#support--caveats">See the Respond.js docs</a> for details.</p>
   <h3 id="respond-import">Respond.js and <code>@import</code></h3>
-  <p>Respond.js doesn't work with CSS that's referenced via <code>@import</code>. In particular, some Drupal configurations are known to use <code>@import</code>. <a href="https://github.com/scottjehl/Respond/blob/master/README.md#support--caveats">See the Respond.js docs</a> for details.</p>
+  <p>Respond.js doesn't work with CSS that's referenced via <code>@import</code>. In particular, some Drupal configurations are known to use <code>@import</code>. <a href="https://github.com/scottjehl/Respond/blob/v3-dev/README.md#support--caveats">See the Respond.js docs</a> for details.</p>
 
   <h2 id="support-ie8-box-sizing">Internet Explorer 8 and box-sizing</h2>
   <p>IE8 does not fully support <code>box-sizing: border-box;</code> when combined with <code>min-width</code>, <code>max-width</code>, <code>min-height</code>, or <code>max-height</code>. For that reason, as of v3.0.1, we no longer use <code>max-width</code> on <code>.container</code>s.</p>
@@ -159,7 +159,7 @@
 
 {% highlight js %}
 // Copyright 2014-2019 Twitter, Inc.
-// Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
+// Licensed under MIT (https://github.com/twbs/bootstrap/blob/v3-dev/LICENSE)
 if (navigator.userAgent.match(/IEMobile\/10\.0/)) {
   var msViewportStyle = document.createElement('style')
   msViewportStyle.appendChild(

docs/_includes/getting-started/grunt.html

@@ -9,7 +9,7 @@
   Then, from the command line:
   <ol>
     <li>Install <code>grunt-cli</code> globally with <code>npm install -g grunt-cli</code>.</li>
-    <li>Navigate to the root <code>/bootstrap/</code> directory, then run <code>npm install</code>. npm will look at the <a href="https://github.com/twbs/bootstrap/blob/master/package.json"><code>package.json</code></a> file and automatically install the necessary local dependencies listed there.</li>
+    <li>Navigate to the root <code>/bootstrap/</code> directory, then run <code>npm install</code>. npm will look at the <a href="https://github.com/twbs/bootstrap/blob/v3-dev/package.json"><code>package.json</code></a> file and automatically install the necessary local dependencies listed there.</li>
   </ol>
 
   <p>When completed, you'll be able to run the various Grunt commands provided from the command line.</p>

docs/_includes/getting-started/license.html

@@ -30,5 +30,5 @@
     <li>Submit changes that you make to Bootstrap back to the Bootstrap project (though such feedback is encouraged)</li>
   </ul>
 
-  <p>The full Bootstrap license is located <a href="{{ site.repo }}/blob/master/LICENSE">in the project repository</a> for more information.</p>
+  <p>The full Bootstrap license is located <a href="{{ site.repo }}/blob/v3-dev/LICENSE">in the project repository</a> for more information.</p>
 </div>

docs/_includes/getting-started/whats-included.html

@@ -5,7 +5,7 @@
 
   <div class="bs-callout bs-callout-warning" id="jquery-required">
     <h4>jQuery required</h4>
-    <p>Please note that <strong>all JavaScript plugins require jQuery</strong> to be included, as shown in the <a href="#template">starter template</a>. <a href="{{ site.repo }}/blob/master/bower.json">Consult our <code>bower.json</code></a> to see which versions of jQuery are supported.</p>
+    <p>Please note that <strong>all JavaScript plugins require jQuery</strong> to be included, as shown in the <a href="#template">starter template</a>. <a href="{{ site.repo }}/blob/v3-dev/bower.json">Consult our <code>bower.json</code></a> to see which versions of jQuery are supported.</p>
   </div>
 
   <h2 id="whats-included-precompiled">Precompiled Bootstrap</h2>