Hi
I have installed the latest version Version 6.1.36 r152435 (Qt5.6.2) on Windows 10 with the extension pack installed. I also have installed an Ubuntu 22.04 with the guest additions. So everything should be fine. But it seems that the guest addition is buggy, because when I resize the window, as you can see in the attached picture, the desktop is not correctly shown. Also, the buttons in the application windows doesn't work.
I have to say that I have the same problem with Ubuntu 20.04 host.