The issue still persists in Ubuntu 20.04. Running mate with lightdm and light-locker configured to lock-on-suspend enabled. After resuming, the desktop contents before suspend are visible for roughly 5 seconds, before the lock screen appears.
As this is absolutely unacceptable in terms of security and privacy, I'm using the following script to suspend (thanks to gethin for the pointer!):
The issue still persists in Ubuntu 20.04. Running mate with lightdm and light-locker configured to lock-on-suspend enabled. After resuming, the desktop contents before suspend are visible for roughly 5 seconds, before the lock screen appears.
As this is absolutely unacceptable in terms of security and privacy, I'm using the following script to suspend (thanks to gethin for the pointer!):
#!/bin/bash r-command -l
mate-screensave
systemctl suspend