Update Wall of Browser Bugs accordingly.
Refs #19670

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See https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/7787318/
Refs #19670

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Refs https://developer.mozilla.org/en-US/docs/Web/CSS/:dir
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See https://bugzil.la/1278000
Refs #19670

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See https://bugzilla.mozilla.org/show_bug.cgi?id=1277782
Refs #19839

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See https://webkit.org/b/158342
Refs #17695.

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Refs https://webkit.org/b/158340
Closes #20012

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Refs https://crbug.com/597642
Closes #19810

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Refs https://webkit.org/b/158276
Closes #19927

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Remove its entry from the Wall of Browser Bugs
Refs #16372

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Remove its entry from the Wall of Browser Bugs.

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Update the Wall of Browser Bugs entry accordingly.

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️️️ https://github.com/twbs/bootstrap/graphs/contributors

Remove its entry from the Wall of Browser Bugs.
Refs #16180

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The `remote` option and the accompanying event have been removed.

Since the "remote" option is no longer available in v4 the reference to the "loaded.bs.modal" event is no longer needed, too.

- Add inverse examples for all variants
- Use rgba() colors for hover and accent states for easy usage in inverse styles

Update tags/labels/badges migration docs to mention class and change in behavior for alignment in list groups

- Really we didn't need to do any of that strip units stuff to generate six new variables, two for each button size
- Using sibling selectors, we can target those split button dropdown toggles using the .dropdown-toggle-split class, and adjust padding and margin as needed
- Now, we nuke the margin-left from the ::after generated caret and tighten up the padding so that those split toggles don't look huge next to their main button

- Includes new class
- New docs to support it
- Rearranged older docs

- Add lighter gray text to disabled state for .form-check
- Separate radios and checkboxes example
- Clarify docs