When scanning a QR code, if its kind is unrecognized, a message similar to this one appears:
(in English: “Scanned QR code text: …”)
NB: this message is identical on all platforms, so this is an issue everywhere. I originally encountered it when trying to log in on the desktop app using my phone’s QR code, which used the BACKUP2 format that wasn’t yet supported by the desktop app. I got a cryptic popup telling me the QR code contents, but no information about why it wasn’t working.
This is really unclear and should be modified to a proper error message, such as: “The QR code you have scanned is invalid. Make sure it has been generated with the Delta Chat app, and that your current app is on the latest version”, with an error icon, etc.
Tangentially, I think the contents of the QR code shouldn’t be displayed by default (the user may not be a developer and will probably be scared by this long string of gibberish) and should be hidden behind a “Show technical details” button/expander.
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