[Bug]: guest mini toolbar shows up on virtualbox host after minimizing guest

[systemdlete]

Version

trunk/main

Host OS Type

Linux

Host OS name + version

Devuan Daedalus (Bookworm)

Host Architecture

x86

Guest OS Type

Linux

Guest Architecture

x86

Guest OS name + version

Alpine 22.03.1, Devuan Daedalus, Devuan Chimaera

Component

GUI

What happened?

Minimizing a fullscreen guest, leaves the mini toolbar displayed on the host screen.

The mini-toolbar is for the last fullscreen guest; windowed guests are not affected in this way. Here, I have just minimized the test-daedalus guest, which can be seen in the running windows applet in the top panel, along with other running VMs. If I open a different fullscreen guest and minimize it, the mini-toolbar will display for that fullscreen guest. For example, if I were to click on the test-alpine window button in the top panel, and then minimize it, the mini-toolbar at the bottom would then relfect the test-alpine guest's menu.

I have tested this on 2 x86 hosts running Devuan Daedalus (bookworm, for reference) and virtualbox 7.2.0, with similar results. This behavior does not occur on an x86 host running Devuan Chimaera (bullseye) and virtualbox 7.2.0.

If this is a new, intended feature, there should be a means to disable it because it is distracting and I am unsure what the purpose of this is. It seems to be dependent on the host OS version which makes this even more puzzling. It may be peculiar to Devuan Daedalus and not Debian Bookworm (I do not have debian installed here, so I cannot test this for comparison.)

The log for the test-daedalus guest is included here, but this seems arbitrary in this context. The issue seems to be related to virtualbox host window management.

test-daedalus-2025-09-18-15-46-39.log.gz

How can we reproduce this?

Install virtualbox 7.2.0 on Devuan Daedalus (or Debian Bookworm perhaps) and minimize a fullscreen guest.
Observe host screen, look for the mini-toolbar.

Did you upload all of your necessary log files, screenshots, etc.?

• Yes, I've uploaded all pertinent files to this issue.

[baserkan]

hello what is your host DE?

[systemdlete]

xfce4

[baserkan]

I see the same think on a Debian 12 host with xfce4 desktop. I don't think guest type is important.

[systemdlete]

@baserkan guest type might be important. Perhaps someone reports that it works successfully on a RH host. We won't know until someone reports a different result on some hosting distro.

But I agree that most likely this is some issue with the drivers on the host side.

[baserkan]

It looks like a Qt related quirk. In most DEs the minitoolbar is minimized as its parent, VM window, is minimized. However something disrupts this on xfce4. Well it is Linux desktop. There is always something...

[baserkan]

Correction. We pass the correct window flag for this mini tool bar to Qt. Qt passes this to the window manager. And as far as I can see there is no requirement for this type of window, NET_WM_WINDOW_TYPE_UTILITY, to be minimized when its parent is minimized. It depends on window manager implementation and it looks like xfce4 decides not to minimize the said widget.

[systemdlete]

Correction to your correction; please re-open (I can't due to permissions). While you may have narrowed down the issue to a particular cause, it does not fix the problem. The mini-toolbar is still appearing at the bottom of the host screen. Until this is either fixed or a work-around is provided, I do not see how this issue can be considered "closed."

Please provide a workaround for this issue. Again, it only occurs on devuan daedalus, and not on devuan chimaera. And this seems to have begun to occur with the latest virtualbox upgrade 7.2.

[baserkan]

So the problem occurs, with 7.2, on devuan daedalus and not on devuan chimaera. right?

[systemdlete]

Any progress on this? Yes, it only occurs with virtualbox 7.2 and only with daedalus, but not chimaera. (I'll be upgrading that chimaera instance to Excalibur (Trixie) in the next month or two, so I may be able to supply additional information then.)

And, please... re-open this. No fix or workaround has been supplied so far.