Add $figure-caption-font-size variable

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Extract $dropdown-item-padding-x variable

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Extract $carousel-control-sm-up-width variable

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Merge branch 'fix-19094' of https://github.com/ameya-pandilwar/bootstrap into ameya-pandilwar-fix-19094

Docs: Add captions above progress bars

Add $small-font-size variable

Add $mark-bg so <mark>'s background-color can be customized independently of $state-warning-bg

Add $label-font-size variable in the name of not hardcoding values

Add $label-pill-border-radius variable

Clarify that $grid-breakpoints are minimum widths for each breakpoint

fixes #19148 as follow up to #19099: ensure local mixin variable is used for  in make-grid-columns mixin

Visual/manual test for checkbox/radio button kbd behavior

Fix typos in documentation - in plural tag names in reboot.md
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Focus (visually hidden) input radio/checkbox

This allows for keyboard navigation (e.g. arrow keys left/right to
trigger different radio buttons) following an initial mouse click
interaction

js/tests/index.html: Replace jQuery event alias methods with functions that throw errors

js/tests/index.html: Replace jQuery event alias methods with functions that throw explanatory errors, instead of with undefined

Refs https://github.com/twbs/bootstrap/pull/19219#issuecomment-184653699

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CONTRIBUTING: Document restriction regarding jQuery event alias methods

Refs #19192
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(as opposed to maximums)

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Extract $dropdown-min-width variable

Introduce $mark-bg variable so that <mark>'s background-color can be customized independently of $state-warning-bg

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Extract $label-pill-padding-x variable

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Extract $label-padding-{x,y} variables