These can be replaced by their `.text-xs-*` parallels.
This also avoids any complications from interactions between the responsive and non-responsive classes.
(e.g. `<div class="text-left text-md-right">`)

Refs #18300
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Now that we don't support IE 8 it's safe to do that.

The table includes a border between the two making this unnecessary

Fixes potential problems with iOS9's new viewport behavior - see for
instance https://forums.developer.apple.com/thread/13510

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Move them to footer, and remove duplicate ones.

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Fix #17173

Fix #17166

Related to #17314.

Before: 1,28 MB (1.351.880 bytes)
After:  1,27 MB (1.341.411 bytes)

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Closes #17319 by merging it.

.visible-xs(-block) => .hidden-sm-up

Fixes #17263.
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update broken holder.min.js link

Fix #17174

- Simpler main nav on all pages
- Back to purple masthead on homepage instead of dark graphite
- Active link styles on the main nav
- Cleaned up sidebar nav
- New docs layout name
- Homepage copy edits
- Updated bright purple docs color

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

Closes #16599 by merging a tweaked version of it.

as role="menu" is a very specific (and strict) ARIA pattern for
desktop-like application menus, and our dropdowns are often used
as pure navigation dropdowns, this change abandons ARIA menus for
a more open-ended and light-weight approach
(see http://heydonworks.com/practical_aria_examples/#submenus and
http://www.w3.org/WAI/tutorials/menus/flyout/#improve-screen-reader-support-using-wai-aria)
note that in dropdown.js, switched to now target ``.dropdown-menu``
instead of ``role["menu"]`` - this also prevents bootstrap scripts
from "bleeding" into non-bootstrap components on the same page.
also removed the ``role=["listbox"]`` part, which appears to be
vestigial/unused (only place in bootstrap that uses that
role are carousels, and their key handling is done separately)

http://www.w3.org/TR/wai-aria/roles#separator

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