To fix the issue, I was forced to switch to KDE Plasma (on the same system). KDE Plasma had no issues with Firefox on both 23.10 and 24.04.
I opened a bug with Mate and there is already a bug report on bugzilla. Unfortunately, no solution was provided so for now Mate + Firefox is not a practical combination. Regarding error msgs and relevant log entries, there are none. The problem seems to be related to DBUS communication between Mate and Firefox. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2047262 Title: Firefox stopped inhibiting screensaver on video playback To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/2047262/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
