I found the culprit, there was a change in the Ubuntu AppIndicator's opacity. Sorry for bad reporting.
** Changed in: gnome-shell (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gnome-shell in Ubuntu. https://bugs.launchpad.net/bugs/1947457 Title: Tray icons not showing unless mouse is over them To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1947457/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs