Also use `viewBox` instead of `viewbox`.

Held babel back due to issues with `objectSpread`.

For some reason the old image was bad quality.

Change `word-break: break-word;` to `word-wrap: break-word;`

This was causing issues for RTL, see https://github.com/twbs/bootstrap/issues/28238

* Remove default kbd element shadow, simplify selector while here

* Add new -shadow-inset variable so our shadows match on .form-control's, .form-select's, and .progress's

* Reuse box-shadow variables for .dropdown's, .popover's, .toast's, .modal's, and .img-thumbnail's

swap jQuery's `trigger(...)` with the more verbose native `dispatchEvent(...)`, as the former may not always behave/bubble correctly (observed while trying to write unit tests for keyboard handling of ARIA tab navigation), which may lead to this test passing even though it fails in real usage.

While #28450 overhauled a ton of forms work, the  support for this custom file input was ineffective. This updates the selector to target the custom field and gray out the entire field.

Fixes #28176.

The previous link is dead one.

Media queries do not support CSS custom properties (CSS variables), so we've had some useless variables lying around since shipping v4. This finally removes them and the associated documentation content that explained the situation.

Fixes #29012.

Corrected minor spelling error.

* Initial spike of consolidated form checks

* Stub out forms rearrangement

- Prepping to drop non-custom file and range inputs
- Prepping to merge custom and native checks and radios (with switches)
- Prepping to merge custom select with form select
- Moving docs arround so forms has it's own area given volume of CSS

* Move input group Sass file to forms subdir

* Start to split and move the docs around

* Simpler imports

* Copyediting

* delete overview file

* Remove commented out code

* remove the custom-forms import

* rewrite flex-check as form-check, replace all custom properties

* Remove old forms doc

* stub out new subpage link section

* update migration guide

* Update nav, forms overview in page nav, and descriptions

* fix check bg position

* fix margin-top calculation

* rename .custom-select to .form-select

* Update validation styles for new checks

* add some vertical margin, fix inline checks

* fix docs examples...

* Revert "Fix readonly-plain-text with button addon (#25871)"

This reverts commit ff40e003.

* Add migration comment

x-ref #28987

Pagination used to have box shadow back in the days which required this property, but nowadays it's redundant. (see https://github.com/twbs/bootstrap/blame/0cd186183c5e18f0517d6037d53f29c56adbac72/less/pagination.less#L17)

- Remove IE10 background hack
- Ability to change the pseudo element
- Ability to change the z-index
- Remove pointer events, just inherit this

Add unit test from #28912 to v5

To fix RGBA borders overlapping issue.