Exiting fullscreen does not restore previous resolution (#18408)

[systemdlete]

I am starting a fresh thread, but this goes back to #18408, "Exiting seamless mode does not revert guest display back to previous resolution -> fixed after (not in) 6.0.4 and in test builds." This is raising its head again, this time in vbox 7.0.8 (package downloaded from virtualbox.org) running in an anti-x 22 VM under a devuan chimaera host. This was not happening when running vbox 6.1.42. Please note that I just upgraded from vbox 6.1.42 directly to vbox 7.0.8; I never upgraded to 6.1.44, nor did I ever install any release of vbox 7.0.x before 7.0.8. I did not change any virtualbox configuration through the upgrade. I simply shut down all my VMs, uninstalled vbox 6.x and installed vbox 7.x, installed the extensions, and restarted the VMs, rebuilt the GA's, and rebooted the VMs again.

The description of the bug is a bit inaccurate; it actual affected returning from fullscreen as well as from seamless mode (I rarely, if ever, use seamless mode). What is most peculiar is that it happens for anti-x but not for devuan, even though they are both derived from debian bullseye. Thus, I am not sure if this is really a problem in vbox, or a different issue within anti-x. I also note that a copy of smartos (which is like illumos) also seems to be OK under the 7.0.8 upgrade.

I have read through the entire thread at viewtopic.php?f=1&t=91111. That conversation ended up with a bug fix. However, I am not sure if this is the same issue, or something else. Attached is the "recipe" for my anti-x 22 VM. It is a test VM running in a testing box, so it is not critical.

One other thing, which might be of note, but maybe not. When I rebooted the anti-x VM after the vbox upgrade, it hung at "Waiting for /dev to be fully populated." I poked around and, after reading numerous posts for this common issue and attempted fixes, one suggested disabling the quiet parameter on the boot line. So that's what I did. The hang still happened, but now I got more info. It was hanging after a slew of messages re DRM. So I thought, maybe this is a video issue of some kind. I disabled 3D (which had been working under vbox 6.1.42) and rebooted again. This time, I got past that hang.

Maybe all of this is somehow related to video driver issues, possibly in anti-x, or maybe I've managed to bring a vbox regression bug back to life. So I am not sure whether to necropost the old thread, or start a fresh thread for what appears to be the same issue.

[EDIT:] The mainboard is a ASUSTeK Computer INC. M5A78L LE which has a built-in video which I am using. Maybe this is useful to you. I am running icewm 3.3.3 (which I think might be the default for anti-x). My devuan chimaera VM is running xfce 4.16.2, just for comparison. My mouse, monitor, and keyboard are being switched via an electronic KVMS switch (but I am not having this issue on my other physical boxes). I am trying to furnish as much info as possible to get this sorted out; happy to provide more if needed.