Sign in throws 400 Bad Request error on some browsers

[MikMik1011]

When I try to log in, Google OAuth2 flow passes and i get redirected to Sched's auth page, however when it sends a request to /sign-in route, on some browsers it gets 200 OK response and authenticates me, however, on some it just throws 400 error and stays stuck on blank page.

I can confirm this bug is present on Chrome on Android, Firefox on Android and Librewolf on Linux.
I managed to get it working on Brave on Linux.

[matijakljajic]

Please help a fallen solider. 🙏

[Ariikitty]

I seem to have a similar issue now except after aproving schej.it to access my calendar when loggin into my google account, it seems to go to a black white page and hang. Refreshing this page makes the sign in button appear in the top right for a split second before going back to a completely white page again.

I have tried this on both Chrome and Firefox on PC and both Chrome and Safari on iPhone using mobile data and all times I have tried, I get the same result