It seems mindbending that this would pass any stage of testing. As a non macOS user, this feels like a complete dealbreaker for ever considering a switch. But macOS is demonstrably popular, and I haven't heard this complaint before. Is it less of an issue in reality than I imagine it would be?
Windows also has problems with mouse clicks and window stacking.
And an ugly bug, when closing a window with the mouse on "x" button, will also close the window below.
