ModEdit; related ticket: #18308: Aero/transparency on Windows Vista no longer working with VirtualBox 6.0.0 r127566
Hello.
VirtualBox Guest Additions version 6.0 as well as version 6.0.2 seem broken on Windows Vista guest, running on VirtualBox version 6.0 or 6.0.2: (Host OS is Windows 10, guest OS has SP-2 installed and is fully patched)
Back to Guest Additions version 5.2.22 and problem is gone, even when running under VirtualBox 6.0.2: Note: In both cases option to install "Direct3D Support" has been enabled, and the question to "install basic Direct3D support instead" was answered with NO – as is required to get Aero working.
(Aero works absolutely flawlessly with Guest Additions version 5.2.22)
Unless Vista support was officially dropped in VirtualBox 6.x, this looks like a severe regression
Regards.