After the upgrade I noticed a few things. Not sure if this is the right place to ask questions about android 13 migration, feel free to remove if needed (I don't have a github or matrix account).
1/ Call in 4g
in System => Network => Internet => FAI, I no longer have the "call in 4g" option. This option was a little below the preferred network type choice. is this an option that disappeared with Android 13?
I know that SeedVault is going to disappear but this one doesn't seem to work. I have the message "backup failed" (translation may be different, I'm not in English).
I tested by restarting, resetting the encryption key, and deleting the .SeedVaultAndroidBackup folder.
Same result. does anyone else have the same?
3/ Fingerprint (Pixel 6a)
I randomly tested to see if the update improved the fingerprint. I can't even make my fingerprints anymore. The sensor seems unresponsive. Fingerprint registration rarely succeeds and is not recognized. I also tested by checking the option in Screen => Increase touch sensitivity, same result. (as @MetropleX said, probably my phone that being).
Thank you very much to all the GrapheneOS team for all the work done!