I were not sure, where this could belong, therefore I chose "Settings". I recently switched from K9 Mail to Thunderbird Mobile and were very happy to see, that there has been a migration option to transfer all the account settings from desktop to mobile version. Well, not all accounts and not all settings were transferred and only the first QR code has been recognized whereas the other three were unrecognizable - but still a good move! That brought me to the idea: Wouldn't it be nice, if there were some Thunderbird Sync, where all accounts, the server settings, the identities (!!), the signatures (!) and other settings (fonts, quoting etc) would be the same on all devices? And where would be the place to promote such an idea?