I'm a long time Clover user, and I decided to give Groupy a try because it seemed like a more overall polished product. However, upon installing it, I came across a glaring bug.
When you have Groupy set to automatically group all windows together, the top of the window glitches out and the tabs disappear. When you move the window, the tabs actually appear behind it and then finally reset itself properly. It only happens upon the first time opening, and combining windows. Anything you combine with it after this works perfectly fine. However, once again... if you close all windows and start the process over, it does it all over again. I have recorded, and uploaded a video to YouTube of this bug. Hopefully Stardock sees this, and is able to rectify the problem!
Also, as a bit of a request, can we please have an option for a window to open with a tab already? Like Clover and QTTabBar does?
Video of said tab bug:
https://www.youtube.com/watch?v=qKEsqolaYnw