* Point to the root migration page which always redirects to the latest version
* Open herodevs link in a new tab
* Update 4.6 docs built from the v4-dev-nes branch
* Change newer version label of v3.3
* Change newer version label of v3.4
* Change newer version label of v4.0/v4.1/v4.2
* Add newer version alert for v4.3
* Add newer version alert for v4.4
* Add newer version alert for v4.5/v4.6 (using `.skippy` bg color)
* Add newer version alert for v5.0 (using `.skippy` bg color)
* Add newer version alert for v5.1 (using `.skippy` bg color)
* Add newer version alert for v5.2 (using `.skippy` bg color)
* Change some copy
- v4 gets 'Bootstrap 5 is here'
- v5 gets 'Theres a newer version of Bootstrap 5'
* Unique message: 'There\'s a newer version of Bootstrap!'
* Change HTML structure for focus visible
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Co-authored-by: Mark Otto <markdotto@gmail.com>