uBO and Mullvad Browser Extension hidden in unified extensions panel
This issue has probably two components:
- what should we do with unified extension system (see: tor-browser#41581 (closed))
- probably due to the unified extension system, the default extension buttons are not displayed by default
I'm perfectly fine with fixing this issue by disabling unified extensions for 13.0 and deal with unified extensions at a later point. (as far as I understand it, unified extensions mostly makes sense for MV3 and parity with Chromium behavior)