Have just the testing of 1.1 a bug with entering the e-mail address found in Firefox 40.0.3. When entering the e-mail address is apostrophe before "@" is inserted.
Did you also this the bug under Win 10 with Firefox 40.0.3?
Thats very strange ... have to look at what could cause that.
Have it to narrow. The bug is only on my laptop. Virus scanners and rootkit scanners found nothing. I think it's the keyboard. The laptop is now over 8 years old. Maybe he wants to retire :o