Last night ( 8 February 2023) I applied the latest Ubuntu 22.04.1LTS OS patches to both my Raspberry Pi-4's using the normal apt utility. Upon successful application of the patches and reboot - both my Pi systems have lost all video output.
Although I can see a brief color map and a few lines of start up messages appear on the monitor, it then goes to completely black when it gets to the point where the logon screen or desktop should appear. The monitor is not reporting "signal loss" or anything at all.
I am not a Linux expert and don't re-install the OS from scratch very often, so everytime I have to do it - it is always a challenge.
I use these systems to run the security camera displays around my house and they are pretty useless with no video output. I still have ssh access, but can't use that to run Firefox for the camera web displays. I tried a few things I found on the web to restore video output, but so far nothing has worked.
It took a long time to get these two Pi systems configured and will probably take me weeks to re-figure it out all over again. I'm sort of hoping for a miracle, where what ever got messed up in the recent OS service would get fixed in a future update - but know that is a long shot.
Thanks for any thoughts or suggestions!