screen content left visible on lock in virtualbox
After the Gnome 3.36 update in Debian Sid, I've noticed that in a VirtualBox environment when the screen lock times out the screen content remains visible until you return and create some activity, at which point the screen content is then immediately replaced with the lockscreen, i.e. it knows it should be locked but the actual lock screen is not shown until user activity occurs.
Host is also Debian Sid. VirtualBox version on host is 6.1.6-dsfg-2. VirtualBox guest version in VM is the same version.
The timeout length in the host happens to be significantly longer than that of the VM.
Before submitting this I made sure to check everything was up to date in both the host and the VM and rebooted the VM; I had the VM up with no applications running, and with the VM in a maximised (non-fullscreen) window. I timed things with a stopwatch, leaving the VM window in focus and did not touch the computer. After the lockscreen timeout of the VM passed with no lockscreen appearing, I continued waiting for the additional minutes until reaching the host lockscreen timeout, whereby the host started dimming the screen in activating its lockscreen. I then moved the cursor to cancel that which also caused an update of the in focus VM, triggering its screen content to be replaced with the lockscreen.