Specifically, the 12.0.4 release focused on "under-the-hood" stability and security rather than major visual overhauls: Security Patches:
Is there a you're seeing in the latest version? Tor Browser 12.0.4 Older Versions for Windows
There are several reasons why you might prefer to use an older version of the Tor Browser: Specifically, the 12
Stay safe, and remember that the Tor Project’s official website (torproject.org) is the only reliable source for both current and archived software. Tor Browser 12.0.4 Older Versions for Windows