This extension is the whole reason I use Firefox instead of Chrome or Brave: Sidebery

This extension is the whole reason I use Firefox instead of Chrome or Brave
https://www.makeuseof.com/sideberry-extension-reason-to-use-firefox-instead-of-chrome-or-brave/

GitHub – mbnuqw/sidebery: Firefox extension for managing tabs and bookmarks in sidebar. · GitHub
https://github.com/mbnuqw/sidebery