[vbox-dev] VM window is hanging on 6.1.17 testbuilds

[GnomeUser]

I am running Linux host and WinXP guest on the recent testbuild 141128
(the bug was also present on 141063) and after a few hours of work the
virtual machine window hangs. The VM is still operational, it can be
pinged and terminated through ACPI shutdown but the hanging window
still stays open even after shutdown. The 6.1.16 release is working
fine. Is this a known bug? Should I investigate further?