Finally got around to upgrading a second computer on my home network to Ubuntu 22.04 LTS, and for the most part the upgrade went well (I had the apparently not-uncommon usrmerge problem, which I worked around by uninstalling usrmerge then reinstalling it), but after I was done ironing out the obvious wrinkles, I discovered a couple of very unusual problems related to remote desktop/remote control.
The first and most irritating of these is that I can no longer access the newly-upgraded computer remotely from my Android 10 phone using RealVNC viewer (VNC Connect by RealVNC version 4.0.1.48856). I can access from another Ubuntu 22.04 LTS computer using Remmina (version 1.4.25). Before the upgrade, both worked fine for what I need: remote access to the running desktop session just as if I sat down at the device and turned on the monitor. After the upgrade, Remmina works as before but RealVNC returns one of several results: sometimes "The connection closed unexpectedly", the "Connecting" message followed by something like "Trying to re-connect" repeatedly (I can't get it to do that one right now, so I can't be sure I've got the wording exactly right), or a black screen with an X mouse cursor, which I can move around but which never resolves to the desktop.
What I've done/confirmed: I'm not using Wayland; sharing, remote desktop, legacy VNC protocol, and remote control are turned on; the user name and password for authentication are what I want them to be; and the computer has been rebooted.
Recommended "similar questions" and results:
Remote desktop via Vnc is black, mouse/keyboard works
Changing picture quality from Automatic to High did not resolve the problem. Other answer is to disable Wayland, which is moot.
Back screen connecting Android VNC Viewer by RealVNC with Ubuntu 22.04 Remote Desktop
Same.
I found a thread that suggested that there might be a problem due to the switch to OpenSSL 3.0, and a different thread (which I can't seem to locate at the moment) which solved it by re-installing OpenSSL 1.1, but I wanted to get advice before trying that, as I assume the reason for the switch was important.
Happy to provide any details/logs/information I've neglected to include. Thanks in advance!
