screensaver locks up and has to be killed

[Ken Sharp]

Sometimes, but not always, when I resume my computer the screen remains blank.

I can switch to another VT (or connect via SSH) and kill mate-screensaver for the user. The system then loads the lock screen, as expected.

At a guess: mate-screensaver doesn't seem to know what's happening after resuming the PC.

I've looked at Bug 1777889 but that seems confused: some claiming the lock screen doesn't show, some claiming what I'm seeing here. The linked upstream bug report is about the screen not locking, which isn't the issue here.

This didn't occur in 18.04, but started when I upgraded to 22.04 via 20.04, so there was nothing tested running 20.04.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: mate-screensaver 1.26.1-1
ProcVersionSignature: Ubuntu 5.15.0-56.62-generic 5.15.64
Uname: Linux 5.15.0-56-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu82.2
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: MATE
Date: Sat Dec 17 23:04:29 2022
SourcePackage: mate-screensaver
UpgradeStatus: Upgraded to jammy on 2022-09-26 (82 days ago)
modified.conffile..etc.apport.crashdb.conf: [modified]
mtime.conffile..etc.apport.crashdb.conf: 2019-08-06T11:56:22.315382

[Ken Sharp (kennybobs)]

Turns out, I've now discovered, that I don't even have to suspend the computer; if the monitor has been switched off for a while, and then switched back on, the screen remains blank and mate-screensaver has to be killed to restore control.

After which I am seeing Bug 1777889.