Trust auth error handling is now much nicer, giving a simple one-line log reason why trust auth failed.

Stack traces in log files are not fun to read when the errors/events should be well understood.
They are appropriate when something went horribly wrong and they are an aid to debugging.
If trust auth fails and there is no username/password auth, the 5xx error screen is displayed.

There might be a reason to have a customized view for this.
Or maybe this is good enough, and the error view can explain what happened.