v4.0.0

Fixes for chrome extension

- Browser vendor detection is set in build-time instead of in runtime.
  "Beginning in Chrome 144, all Chrome Extension APIs are also available
  under the browser namespace". The attributes browser and chrome was
  used to distinguish between Mozilla and Chrome.
- Fix identificaton of bookmarks built-in root folders. Bookmark id
  is not fixed anymore, instead use folderType available from Chrome 134.
  Bump major version since this breaks backward compatibility.