.. and maybe other platforms as well (though X11 was not affected)?
The issue was that passing a higher resolution than the current desktop
resolution to SDL_CreateWindow() with SDL_WINDOW_FULLSCREEN didn't switch
to that resolution (even though it did switch to lower resolutions).
When creating a fullscreen window, window->fullscreen wasn't even set
at all (only zeroed out), setting it only happened if the user explicitly
called SDL_SetWindowDisplayMode(). So without that, SDL_CreateWindow()
-> SDL_UpdateFullscreenMode() -> SDL_GetWindowDisplayMode() used the
resolution from window->windowed.w/h which were limited to the desktop size
due to some weird combination of WIN_AdjustWindowRectWithStyle() and
WIN_WindowProc() being called after a call to SetWindowPos().
fixes#3313
72d8128520