I posted an update on GitHub yesterday with the current status, Bitwarden 1.25.0 Extension not showing in Safari 14.0.3 on macOS 11.2.3 · Issue #1718 · bitwarden/browser · GitHub. In short we suspect the issue is a corrupt database in the Launcher Service on MacOS.
There are three current work-arounds:
- OnyX and similar tools supports rebuilding the Launch Services database.
- Install Safari Technical Preview, it seems to register itself as the new handler for Web Extensions. Which also makes the extensions available in the regular Safari application.
- The following command seems to rebuild the Launch Services database and worked on my machine
/System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Support/lsregister -kill -r -domain local -domain system -domain user
. Note the command should be run in the terminal as the affected user. The machine may temporarily slow down and finder can take a moment to become responsive while it rebuilds the database again.