How comes I didn’t see the 4.2 update sooner, I was sure I checked. Applying it immediately !
that said, I see there are new fixes for auth token refresh in accountmanager, so let’s see if a v4.3 is needed. The long march to Oauth2
After I installed the update to 4.2, everything seems to work now, no authentification error up to now (on Fairphone 6). Thank you to the developers!