Chuck Smith had something work the way he might want it, but was sure it wasn’t supposed to work that way. After news broke of the Yahoo account hacking, he changed his password on his Mac. But when he went to his iPhone and iPad mini, he found they’d already updated account information.
However, he made the change in his macOS Firefox browser—not in Safari and not via the Internet Accounts system preference pane.
So how did my iOS devices quickly know that my Yahoo account password had been changed? The only thing I can figure is some new behind-the-scenes cooperation between Yahoo and Apple, and that makes me wonder if Apple is also coordinating in like manner with other email providers, such as Gmail.
As far as I can tell, there’s no way for this to happen, which makes it baffling that it did. Many Firefox users would like to have iCloud Keychain integration, and have commented about this all over for years. It’s possible that with the Yahoo app installed in iOS, some magic may have occurred. (I’ve got Yahoo configured to use the app as the only way to login, so I can’t test this. In that configuration, you enter your username on the web or in another app, and you confirm the login via the smartphone app, no password required.)
If you use Safari and iCloud Keychain (enable it in the iCloud system preference pane), you can have automatic sync of all your passwords and account information across every device logged into the same iCloud account that also has iCloud Keychain enabled.
I like iCloud Keychain, because Apple built it in such a way that even though it syncs across iCloud, none of the unencrypted data ever winds up there. It passes secrets around among your connected devices, so that only they have the encryption key; encryption items pass through iCloud with some metadata about modification times that keeps them up to date.
Readers, have you seen this kind of mysterious outside-of-Safari sync, too?
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