OAuth login works here both with Firefox and Chrome, Linux and Windows. I've tested on macOS with Safari, but that was a while back.
On linux the critical part is that the .desktop file is installed and the "mimetype" entry contains x-scheme-handler/tidal.
For Windows Tidal must exist as a URL Protocol in the registry, this should be done by the setup https://github.com/strawberrymusicplayer/strawberry/blob/db6aac603c7f557731a1ba3a13817e9c3b69770a/dist/windows/strawberry.nsi.in#L701
This conflicts with the official Tidal app, so if you installed the Tidal app after you installed Strawberry, it will probably stop working with Strawberry.
But this doesn't get triggered before you get a successful login on Tidal when forwarded to Tidal by Strawberry. if you get an error there, the App ID could be wrong.
I don't remember where I got the App ID from. It was long ago, 2018 I think.
