Few regressions on dropdowns

Prerequisites

• I have searched for duplicate or closed issues
• I have validated any HTML to avoid common problems
• I have read the contributing guidelines

Describe the issue

Some regressions can be observed apparently after https://github.com/twbs/bootstrap/commit/bb7664db0aea2dddbc637992d2d0e78632dc2e68.

1. The new feature of centered dropdowns and centered dropup doesn't work anymore (see https://github.com/twbs/bootstrap/commit/c0f30366ace5f607e0b70a0e0034d2e8254bad9b). The menus are not centered:
   • Centered: not centered
   • Dropup centered: not centered and points to the bottom

Note: those previews are based on https://github.com/twbs/bootstrap/pull/35948 after the adding of the missing .dropup.

2. Escape event is propagated to the parent element (e.g. Offcanvas in https://twbs-bootstrap.netlify.app/docs/5.1/components/offcanvas/#live-demo):

• Go to https://twbs-bootstrap.netlify.app/docs/5.1/components/offcanvas/#live-demo
• Click on link with href button
• Press Tab until you get focus on dropdown
• Open it with Enter
• Press Esc: the Offcanvas closes itself and shouldn't; only the dropdown should collapse

What operating system(s) are you seeing the problem on?

Windows, macOS

What browser(s) are you seeing the problem on?

Chrome, Firefox

What version of Bootstrap are you using?

v5.2.0 (current main branch)