@aes__ The Window title bar remains visible on the screen (it "rolls up" the window leaving only the title bar visible). If you have a small window over a larger window, it lets you quickly glance at what's beneath it and then return it to it's original state. But that's all you can do is glance, evidently. You can't click on the larger window that was in the background (at least not on Mint) because that effectively minimizes the rolled up window.