Yep, same issue. It's not ios13 though. Downloading to photos and playing them is fine. It's the xfinity mail app as far as I can tell.
another recent thing I've noticed about the mail app is if you leave it open and go do something else for a while and you come back to it, it often won't download the mail, you can see the subject and header, you have to close and restart it.
This was a known bug in iOS 13. They tried a new method for managing the device's memory, but it just ended up killing apps that were running in the background.