If using Microsoft Authenticator instead of Google the button to open Authenticator tries to open the MS app but fails with error ‘secret key invalid’ . Ignoring this error allow the app to be opened and a code obtained. On return to QFapp the code is automatically pasted and the app authenticates ok. It would seem with a little investigation QF could fully support MS Authenticator which is becoming more widely used due to its tight integration and additional password management faculties.