Comment 8 for bug 1893624

Yes I figured that out, managed to uninstall and remove the default kernel (5.4) and the 'bad' one (5.8.5).

Only 2 minor issues remaining:
1) Brightness setting is not persistent after reboot (it was with 5.8.5).
When I turn brightness down using the quick keyboard button, it goes immediately to almost lowest, so the % of brightness is stored in the OS, but the screen itself booted with max brightness.

2) Hibernation does not work:
$ sudo systemctl hibernate
Failed to hibernate system via logind: Not enough swap space for hibernation
Even though my /swapfile is 6.4 GB (40% of 16GB) and only 20% of my RAM is in use.

Not big issues, since I can adjust brightness and I can use suspend.