[ci skip]

Refs #15947

[ci skip]

Closes #16039.

affix plugin does not work within a pulled/pushed column

[ci skip]

Fix radio button toggle behavior for keyboard users

Fixes #16269.
Closes #16301 by merging a rebased version of it.

This documents the limitation discussed in https://github.com/twbs/bootstrap/issues/12126:

> When using column reordering and using the affix-plugin on an element positioned with push, the affix plugin doesn't work correctly - the element affected by the affix plugin is positioned to the left even when the element is in a column positioned on the right.

Seems to affect Safari (tested in version 8) only.

That issue has (unfortunately) been closed, so this at least documents the behavior.

Make .btn in .btn-toolbar float:left too

Add px unit to perspective property value

Reset text/font properties more thoroughly for tooltips+popovers

[skip sauce]
[skip validator]

as this breaks keyboard navigation for radio button toggles (see
https://github.com/twbs/bootstrap/issues/16223)

Use .dropdown-menu instead of ARIA roles for dropdown keydown event handler

Add Wall of Browser Bugs entries for #16180

Closes #16180.

rm defunct workaround for OS X Chrome <select> printing bug

Chrome fixed the bug several versions ago
(see https://github.com/twbs/bootstrap/issues/11245#issuecomment-57494756 )
thus rendering this workaround unnecessary.

[skip sauce]

[skip sauce]

Add grunt-contrib-htmlmin.

Only used for the GitHub docs.

Upgrade to Holder v2.5.2

[skip sauce]