Surface input region not handled correctly on Windows
On Windows, clicking near the outside of GtkPopovers has no effect at all. That's because we do not correctly take in account the input region when handling the WM_NCHITTEST message.
As an example, in gnome-calculator, clicking the Advanced
button placed in the title bar has no effect, because the GtkPopover surface lies above it:
Edited by Luca Bacci