Nicholas Ib Said:
”I'd still like Apple to fix this issue however!”
Screensharing Via iPhone Camera App:
Have you screenshared this with Apple? Just using your Mac to screenshare, this Mail window would just get in way, intermittently, so it seems.
So, call Apple and ask to talk to an Apple Rep. Screenshare your camera of your iPhone with the Apple Rep, allowing them to see this from your perspective.
How To: With the Camera App open, enable Speaker Phone, and request a prompt from the Apple Rep to enable screensharing. Point out what issues you have come across, as you share the phone screen. Perhaps, even, this can be fixed upon doing so.
So, troubleshoot this using screensharing on your iPhone, if an option in your area:
Contacting Apple:
Contact Us - Choose Locations
USA: 1(800)MY-APPLE