:(

Are you on mobile by any chance?

If you could try again. I fixed a few small things, and I haven't seen the error since. Unfortunately it seems to manifest sporadically on mobile. I have a feeling there's something in the callback URL I get when authenticating through the mobile app... but still can't pinpoint it 100%

You could also clear your cookies - in case you managed to log-in the previous time and they got set.