Shouldn't really happen, but China for example has blocked Google so this should help.

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And add explanatory comments to the Carousel & Dashboard examples regarding holder.js

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Fix issue #15601 — Position of X-UA-Compatible, charset and viewport

Add comment to all examples

The non-responsive is correctly saying 2 instead of 3

plus one example that still used the old <div role="navigation"> and a
fix-up of the callout as per
https://github.com/twbs/bootstrap/issues/15109

Closes #14951 by merging it.

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Added handling of aria-expanded=true/false to collapse.js, updated
documentation to include advice on making expand/collapse controls
accessible, updated examples and javascript documentation to use
aria-expanded and aria-controls (when targetting single collapsible
element, using ID rather than class selector)

Closes #14147.
Closes #14153.

This way, it works in all browsers.

The validator doesn't choke anymore on this and even though it's not spec compliant, it's needed for some IE versions. So until we move favicon.ico in root, this should do the job.

Closes #13379.

If you add an "active" class to one of the <li> elements in the top navigation, and style it so that active tabs have a different color, it becomes clear that there is a 1 pixel stray line under the navigation. This style fixes that.

Follow up to 1bdd59b18c2d1b2409d0422a60e8c007053202df, to better position the sidebar so the potential scrollbar doesn't get hidden by the navbar

Fixes #12435

Also, use Google's CDN per #11369.

Replaces links to holder.js with links to the new docs.min.js.
The uncompressed holder.js file is now in docs/assets/js/vendor,
which is excluded from Jekyll builds. In turn, Holder is now
included in docs.min.js, which is smaller than holder.js,
so this should make everybody happy. :)