This is a new Opera developer update.
The most important fixes:
- Video pop-out button now works properly on twitch.tv
- [Linux] Fixed inability to exit full screen mode
- [Mac] Fixed crash when opening the tab menu
- [Mac] Navigation with keys now works with opened toolbar
- [Windows] Number of closed tabs in O-menu history is now correct
Chromium has been updated to 79.0.3945.16.
See the full changelog.