Regarding the suggestion to update to Linux 6.6, I entered
sudo mhwd-kernel -i linux66
but get the error:
(6/6) Updating Grub-Bootmenu
/etc/default/grub: line 9: optimus-manager.startup=nvidia: command not found
error: command failed to execute correctly
I don’t recall intentionally removing optimus-manager. I did some time ago change the BIOS setting to use the nvidia card only – the switchable graphics was giving me too much grief. Any suggestions?