It's great if you just use one window, but the multi-window behavior is so undesirable that I had to stop using this. The window behavior is nothing like the tab behavior. Here's how it should work. A group should be able to span multiple windows (it can't). When you select a group, it should close any windows that do not contain any tabs within that group. That way, the only tabs you have open across all windows are the tabs in that tab group. This would give behavior that is consistent with tabs. But now there's this half baked solution where you can have a different tab group open in every window and it's even harder to figure out what's going on. The whole point of having multiple windows is so I can look at multiple windows at the same time. Otherwise I would just use tab groups instead of windows! With the current solution, you can't have two windows side by side that make sense with each other. It feels totally random which windows get which tab groups assigned to them. A group is supposed to represent the only things I want to have open at once, which should be able to include multiple side by side windows together in the same group that get opened and closed together when I switch groups.