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datahoarder
Who are we?
We are digital librarians. Among us are represented the various reasons to keep data -- legal requirements, competitive requirements, uncertainty of permanence of cloud services, distaste for transmitting your data externally (e.g. government or corporate espionage), cultural and familial archivists, internet collapse preppers, and people who do it themselves so they're sure it's done right. Everyone has their reasons for curating the data they have decided to keep (either forever or For A Damn Long Time). Along the way we have sought out like-minded individuals to exchange strategies, war stories, and cautionary tales of failures.
We are one. We are legion. And we're trying really hard not to forget.
-- 5-4-3-2-1-bang from this thread
ok, but we're talking about testing backups, which isn't this.
The process with a new phone (I just had to do this due to water damage) is put SIM in new phone, then it logs in and asks if you want to restore from the backup (you need to enable file access first) and then it restores from a hidden area of your Google account.
I saw your edit and replied to it - that backup is still inaccessible other than via WhatsApp, although I guess it's a comfort to see that they're there.
You'd linked "How to transfer your chat history", which isn't testing the backup. If you deleted the data in the emulator, you'd need to login again to test the backups, which puts you back needing a SIM.