Firefox 89 Beta Released with UI Changes

The Mozilla release notes:https://www.mozilla.org/en-US/firefox/89.0beta/releasenotes/

I wonder what this means:

"Changed: Introducing a non-native implementation of web form controls, which delivers a new modern design and some improvements to page load performance. Watch for layout bugs in web pages that make assumptions about the dimensions or styling of form controls."

A very visible change is the default styling of the form elements (input, button): more rounded, with a strong double blue outline when focused. I wonder if this is supposed to reflect the style changes of the UI itself.

I don't see any changes in the stupid UI. I need a menu, i want the titlebar of the window to be free of crap, i want 1 click for bookmarks, i want the settings easily accessible.