So, I migrated from an iPhone 11 to 13, and
that was a bit rockier than I had hoped, but mostly fine.
Now, towards the end of that phone-to-phone transfer, iOS asked me if I wanted to reset the old device. I'm pretty sure I said no. But!
- I now tried to use Threema's guide to migrate to the new phone. It only migrated… some of the data?? OK. Let's ignore that.
- More importantly, Google Authenticator is completely confused now. Both the old phone and the new phone think they're fresh, and if I tap "import existing accounts" on the old(!) device, it asks me to open the app on the old device. Uh-oh.
How do I convince Google Authenticator that it is, in fact, the correct device? Does restoring from an iCloud backup help, or make it worse?
(I might still have it working on my even older iPhone 8…)