edo0

 Sorry, I cannot reproduce your issue on Arch (Xorg, MATE DE). I need more information on the system, and possibly a picture

@xfzv thank you very much for your report! I can confirm that with the latest Firefox on Arch I can reproduce the issue as well. Unfortunately in these months I...

Interesting suggestion, but is there any reason why you would suggest MPL over the more established and widely respected GPLv3?