Heya, I think I got to the root cause of that issue and I deployed an updated version that (hopefully) fixes it.
If you would still like to give it another shot I would appreciate it :)
If you would still like to give it another shot I would appreciate it :)
I think it might be because you have third-party cookies disabled [1], and the Google Auth client uses an iframe with cookies to do its thing. I replicated it myself by disabling third-party cookies and the results were similar to what you described.
I'll look into what I can do about this on my end tomorrow. Thank you again for your time!