For the past week or so (Firefox app was last updated around 1st September I believe), my Sony XZ2 phone has restarted itself after saving a picture off the Internet. The new update today didn't fix it. The phone screen goes blank, then the background reappears with the app icons and it reconnects to the internet again. Just like pressing the restart button but much quicker. I've tried other Internet browser apps with saving the same picture and not had it happen. Not sure if it's just a coincidence that the problem has coincided with the last update though.