Hi again and thank you for the answer.
I've been using Linux as my main OS only for 5 months, so I wasn't entirely sure which package I should've pointed the bug report to. I intended to create it for amd GPU drivers, but I didn't know at that point, that they are like firmware packages in Linux. So yes, it certainly went to wrong place.
And even if it would've gone to the GPU drivers, it still most likely would've been wrong as you mentioned.
I think you were correct at what was causing the problem. It most likely was the bug related to the OBS screen capture. I've been using it on the background almost all the time and the crash usually happened, while I was playing some game with Bottles.
I switched back to Wayland after you mentioned that the bug might've been fixed, and I haven't had single similar system crash after that. So if this bug report is still open, it can be closed now.
Thank you for the help, it was much appreciated!