I can confirm the AMD bug. I’ve had similar issues after the update and reported back in this discussion. It was split off into a separate support topic:
System freeze (amdgpu - flip_done timed out) after switch to kernel 6.12
I’ve also reported the bug in the AMD Gitlab for their OS driver but haven’t heard back. It’s a long running issue (it seems) and it doesn’t come as a surprise that I’m not the first one to report it. 
A short-term solution for me seems to be to shut off the monitor and switch it back on. The system comes back after some seconds which saves the session and avoids a restart. Upon further testing I’ve noticed, powering off the monitor is not necessary.
Just switch to another virtual terminal like CTRL+ALT+F3 and wait for a while (20-25? seconds). The screen goes black and switches the terminal. Afterwards without logging into the new terminal just switch back to the DE session with CTRL+ALT+F2. The session should still be there to continue.