Fix broken and redirected links.

docs/_includes/nav-docs.html

@@ -17,7 +17,7 @@
     {% if slug == "examples" %}
         <a class="bd-toc-link" href="{{ site.baseurl }}/{{ group.title | downcase | replace: ' ', '-' }}/">
       {% else %}
-        <a class="bd-toc-link" href="{{ site.baseurl }}/{{ group.title | downcase | replace: ' ', '-' }}/{{ link.title | downcase | replace: ' ', '-' || page.title | downcase | replace: ' ', '-'  }}">
+        <a class="bd-toc-link" href="{{ site.baseurl }}/{{ group.title | downcase | replace: ' ', '-' }}/{{ link.title | downcase | replace: ' ', '-' || page.title | downcase | replace: ' ', '-'  }}{% if link.title || page.title %}/{% endif %}">
       {% endif %}
         {{ group.title }}
       </a>

docs/about/history.md

@@ -10,4 +10,4 @@ Originally created by a designer and a developer at Twitter, Bootstrap has becom
 
 Bootstrap was created at Twitter in mid-2010 by [@mdo](https://twitter.com/mdo) and [@fat](https://twitter.com/fat). Prior to being an open-sourced framework, Bootstrap was known as _Twitter Blueprint_. A few months into development, Twitter held its [first Hack Week](https://blog.twitter.com/2010/hack-week) and the project exploded as developers of all skill levels jumped in without any external guidance. It served as the style guide for internal tools development at the company for over a year before its public release, and continues to do so today.
 
-Originally [released](https://blog.twitter.com/2011/bootstrap-twitter) on [<time datetime="2011-08-19 11:25">Friday, August 19, 2011</time>](https://twitter.com/mdo/statuses/104620039650557952), we've since had over [twenty releases](https://github.com/twbs/bootstrap/releases), including two major rewrites with v2 and v3. With Bootstrap 2, we added responsive functionality to the entire framework as an optional stylesheet. Building on that with Bootstrap 3, we rewrote the library once more to make it responsive by default with a mobile first approach.
+Originally [released](https://blog.twitter.com/2011/bootstrap-from-twitter) on [<time datetime="2011-08-19 11:25">Friday, August 19, 2011</time>](https://twitter.com/mdo/statuses/104620039650557952), we've since had over [twenty releases](https://github.com/twbs/bootstrap/releases), including two major rewrites with v2 and v3. With Bootstrap 2, we added responsive functionality to the entire framework as an optional stylesheet. Building on that with Bootstrap 3, we rewrote the library once more to make it responsive by default with a mobile first approach.

docs/components/card.md

@@ -513,7 +513,7 @@ Cards can be organized into [Masonry](http://masonry.desandro.com)-like columns
 
 Only applies to small devices and above.
 
-**Heads up!** This is **not available in IE9 and below** as they have no support for the [`column-*` CSS properties](https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Using_multi-column_layouts).
+**Heads up!** This is **not available in IE9 and below** as they have no support for the [`column-*` CSS properties](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Columns/Using_multi-column_layouts).
 
 {% example html %}
 <div class="card-columns">

docs/components/forms.md

@@ -585,7 +585,7 @@ Add the `disabled` attribute to a `<fieldset>` to disable all the controls withi
 {% callout warning %}
 #### Caveat about link functionality of `<a>`
 
-By default, browsers will treat all native form controls (`<input>`, `<select>` and `<button>` elements) inside a `<fieldset disabled>` as disabled, preventing both keyboard and mouse interactions on them. However, if your form also includes `<a ... class="btn btn-*">` elements, these will only be given a style of `pointer-events: none`. As noted in the section about [disabled state for buttons]({{ site.baseurl }}/buttons/#disabled-state) (and specifically in the sub-section for anchor elements), this CSS property is not yet standardized and isn't fully supported in Opera 18 and below, or in Internet Explorer 11, and won't prevent keyboard users from being able to focus or activate these links. So to be safe, use custom JavaScript to disable such links.
+By default, browsers will treat all native form controls (`<input>`, `<select>` and `<button>` elements) inside a `<fieldset disabled>` as disabled, preventing both keyboard and mouse interactions on them. However, if your form also includes `<a ... class="btn btn-*">` elements, these will only be given a style of `pointer-events: none`. As noted in the section about [disabled state for buttons]({{ site.baseurl }}/components/buttons/#disabled-state) (and specifically in the sub-section for anchor elements), this CSS property is not yet standardized and isn't fully supported in Opera 18 and below, or in Internet Explorer 11, and won't prevent keyboard users from being able to focus or activate these links. So to be safe, use custom JavaScript to disable such links.
 {% endcallout %}
 
 {% callout danger %}

docs/components/list-group.md

@@ -46,7 +46,7 @@ Add badges to any list group item to show unread counts, activity, etc.
 </ul>
 {% endexample %}
 
-When in flexbox mode, you'll need to rearrange the contents of your list group items. To replicate the right-aligned badges as shown above, use the following example's code. Note the [`flex-items-xs-between` utility class](/layout/flexbox-grid/#horizontal-alignment), the badge's placement, and the lack of a float utility on the badges.
+When in flexbox mode, you'll need to rearrange the contents of your list group items. To replicate the right-aligned badges as shown above, use the following example's code. Note the [`flex-items-xs-between` utility class]({{ site.baseurl }}/layout/flexbox-grid/#horizontal-alignment), the badge's placement, and the lack of a float utility on the badges.
 
 {% highlight html %}
 <ul class="list-group">

docs/getting-started/accessibility.md

@@ -23,7 +23,7 @@ In addition, groups and toolbars should be given an explicit label, as most assi
 
 ## Skip navigation
 
-If your navigation contains many links and comes before the main content in the DOM, add a `Skip to main content` link before the navigation (for a simple explanation, see this [A11Y Project article on skip navigation links](http://a11yproject.com/posts/skip-nav-links)). Using the `.sr-only` class will visually hide the skip link, and the <code>.sr-only-focusable</code> class will ensure that the link becomes visible once focused (for sighted keyboard users).
+If your navigation contains many links and comes before the main content in the DOM, add a `Skip to main content` link before the navigation (for a simple explanation, see this [A11Y Project article on skip navigation links](http://a11yproject.com/posts/skip-nav-links/)). Using the `.sr-only` class will visually hide the skip link, and the <code>.sr-only-focusable</code> class will ensure that the link becomes visible once focused (for sighted keyboard users).
 
 {% callout danger %}
 Due to long-standing shortcomings/bugs in Internet Explorer (see this article on [in-page links and focus order](http://accessibleculture.org/articles/2010/05/in-page-links/)), you will need to make sure that the target of your skip link is at least programmatically focusable by adding `tabindex="-1"`.
@@ -47,10 +47,10 @@ Note that this bug will also affect any other in-page links your site may be usi
 
 When nesting headings (`<h1>` - `<h6>`), your primary document header should be an `<h1>`. Subsequent headings should make logical use of `<h2>` - `<h6>` such that screen readers can construct a table of contents for your pages.
 
-Learn more at [HTML CodeSniffer](https://squizlabs.github.io/HTML_CodeSniffer/Standards/Section508/) and [Penn State's Accessability](http://accessibility.psu.edu/headings).
+Learn more at [HTML CodeSniffer](https://squizlabs.github.io/HTML_CodeSniffer/Standards/Section508/) and [Penn State's Accessability](http://accessibility.psu.edu/headings/).
 
 ## Additional resources
 
 - ["HTML Codesniffer" bookmarklet for identifying accessibility issues](https://github.com/squizlabs/HTML_CodeSniffer)
 - [The A11Y Project](http://a11yproject.com/)
-- [MDN accessibility documentation](https://developer.mozilla.org/en-US/docs/Accessibility)
+- [MDN accessibility documentation](https://developer.mozilla.org/en-US/docs/Web/Accessibility)

docs/getting-started/browsers-devices.md

@@ -168,7 +168,7 @@ Confirm the document mode by opening the debugging tools: press <kbd>F12</kbd> a
 
 This tag is included in all of Bootstrap's documentation and examples to ensure the best rendering possible in each supported version of Internet Explorer.
 
-See [this StackOverflow question](https://stackoverflow.com/questions/6771258/whats-the-difference-if-meta-http-equiv-x-ua-compatible-content-ie-edge) for more information.
+See [this StackOverflow question](https://stackoverflow.com/questions/6771258/what-does-meta-http-equiv-x-ua-compatible-content-ie-edge-do) for more information.
 
 ## Internet Explorer 10 in Windows Phone 8
 

docs/getting-started/build-tools.md

@@ -11,7 +11,7 @@ Bootstrap uses [Grunt](http://gruntjs.com) for its CSS and JavaScript build syst
 
 To use our Gruntfile and run our documentation locally, you'll need a copy of Bootstrap's source files, Node, and Grunt. Follow these steps and you should be ready to rock:
 
-1. [Download and install Node](https://nodejs.org/download), which we use to manage our dependencies.
+1. [Download and install Node](https://nodejs.org/download/), which we use to manage our dependencies.
 2. Install the Grunt command line tools, `grunt-cli`, with `npm install -g grunt-cli`.
 3. Navigate to the root `/bootstrap` directory and run `npm install` to install our local dependencies listed in [package.json](https://github.com/twbs/bootstrap/blob/master/package.json).
 4. [Install Ruby][install-ruby], install [Bundler][gembundler] with `gem install bundler`, and finally run `bundle install`. This will install all Ruby dependencies, such as Jekyll and plugins.

docs/getting-started/contents.md

@@ -25,7 +25,7 @@ bootstrap/
     └── bootstrap.min.js
 {% endhighlight %}
 
-This is the most basic form of Bootstrap: precompiled files for quick drop-in usage in nearly any web project. We provide compiled CSS and JS (`bootstrap.*`), as well as compiled and minified CSS and JS (`bootstrap.min.*`). CSS [source maps](https://developer.chrome.com/devtools/docs/css-preprocessors) (`bootstrap.*.map`) are available for use with certain browsers' developer tools.
+This is the most basic form of Bootstrap: precompiled files for quick drop-in usage in nearly any web project. We provide compiled CSS and JS (`bootstrap.*`), as well as compiled and minified CSS and JS (`bootstrap.min.*`). CSS [source maps](https://developers.google.com/web/tools/chrome-devtools/javascript/source-maps) (`bootstrap.*.map`) are available for use with certain browsers' developer tools.
 
 ## Bootstrap source code
 

docs/layout/overview.md

@@ -47,7 +47,7 @@ Use `.container-fluid` for a full width container, spanning the entire width of
 
 ## Responsive breakpoints
 
-Since Bootstrap is developed to be mobile first, we use a handful of [media queries](https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Media_queries) to create sensible breakpoints for our layouts and interfaces. These breakpoints are mostly based on minimum viewport widths and allow us to scale up elements as the viewport changes.
+Since Bootstrap is developed to be mobile first, we use a handful of [media queries](https://developer.mozilla.org/en-US/docs/Web/CSS/Media_Queries/Using_media_queries) to create sensible breakpoints for our layouts and interfaces. These breakpoints are mostly based on minimum viewport widths and allow us to scale up elements as the viewport changes.
 
 Bootstrap primarily uses the following media query ranges—or breakpoints—in our source Sass files for our layout, grid system, and components.