For some reason window focus behaves a bit oddly. Perhaps it’s a SDL on Mac specific issue.
I have two windows. When I switch to another app, and click on one of the windows, always one window (the main window?) pops to the front. This could be the window I clicked on, but often it’s not, and the window I clicked (which was on top of the ‘main’ window) disappears to the background and I have to click it again to give it focus. Do you also see this issue on Windows? Is it something SDL related, or does Nap do something w.r.t. sending windows to the front when the app is foregrounded?