GPU hang
I recently experienced some GPU hangs. Journalctl asked me to file a new bug report, so this might possibly a duplicate.
So what I experience rather frequently recently is that my computer sometimes just freezes, especially often when the screen is locked. However, today I got "lucky" and it happened while using thunderbird.
Interesting to note is that while my computer seemed to be irresponsive, I could change to tty5 using a keyboard shortcut. However, changing took more than a minute. Once using tty5 I could use my computer in non-graphical mode freely, as if nothing had happened. I could also switch back and forth to tty1, where a gnome login screen welcomed me. However, whenever I switched back to my original frozen gnome session at tty2 my computer would freeze again and it would take a long time to get back to tty5.
For system information: up-to-date Fedora 31 with kernel 5.4.7-200.fc31.x86_64, using default gnome desktop.
Attached are a shortened journalctl output as well as /sys/class/drm/card0/errorgpu-error