Invisible windows in VirtualBox

Submitted by Daniel Ruiz de Alegría

Assigned to Olivier Fourdan @olivier

Link to original bug (#16274)

Description

Created attachment 9306 Xfwm shows invisible windows

Many people are reporting not being able to use their desktop as xfwm4 is showing completely transparent windows, usually only drawing the shadow frame. This issue appears using Virtualbox over a Windows Host, having 3D acceleration enabled and guest-additions installed. Testing it on a Linux Host, windows showed correctly, but some glitches appear in the form of fast blinking.

In both cases disabling 3D acceleration solves it. But other tested compositors like Compton don't show this behavior.

This has been tested on Kali Linux 2019.4 and Xubuntu 19.10, using xfwm4 4.14. But the issue was introduced in version 4.13.0 as 4.12.0 works fine.

Compiling it from source showed that the change that introduced this bug is 'compositor: Add support for GLX' https://git.xfce.org/xfce/xfwm4/commit/?id=fee08eafa751a153ff93b04152ea66334141cac5

Attachment 9306, "Xfwm shows invisible windows":

Version: 4.13.0