When watching youtube on Firefox, Youtube become increasingly slow after a couple of hours (rendering the page and seeking becomes unresponsive). This can be expedited by also starting a movie in VLC.
After a while the system just hangs, I can still see the desktop and hear music playing. The mouse cursor can be moved. I can also still start a terminal session with e.g. ctrl+alt+F2.
I have no idea how to troubleshoot this. From what I can gather from my system is that I have enough free memory (about 48GB available), the cpu is not taxed at all and the temperatures are ok.
Generally the system is very stable and I have no problems running the Dead Space Remake, Total Warhammer 3, Diablo Resurrected.
The issues started happening about a month ago, hard to tell. Before this the system has been running stable for over 2 years now.
I started using Firefox again a few days ago (I had been using Chromium for several years before that). The first thing I noticed after a while was exactly what you are describing here. My immediate reaction was: Firefox has finally pulled up its heels. It was a completely new profile without any legacy issues. Ideology and data protection aside - this is what drives users straight to Chromium and its derivatives and I can understand that very well.
Ah clear, might it have been that Google is pushing the AV1 encoding instead of their own format recently? I’ll have a look if there is an addon that forces the use of a different format.
Well that did not solve the problem. I disabled av1 in Firefox entirely.
When it happened I check RAM and VRAM. I was using around 18/64GB RAM and 1.3/24GB VRAM. Seems that is not the problem.
I tried restarting my display manager LightDM. This results in a login screen, but as soon as I login (on ctrl+alt+F7) the screen stays black and I only see the mouse cursor.