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I can't produce a logcat except in cases where the app crashed. I've opened other issues too though

Just connect the phone and send me the logcat while signing, if you have an adb I have some specific things being logged, hopefully they exist. Mostly won't but just might help me if there is some weird error suppressed. I'll look into them.

I don't I can extract that logcat information. To do that, my phone needs to be rooted and it'll break manufacturers warranty

oh ok, not a problem.

I'll find a way though.