Raspberry Pi OS (previously known as Raspbian) version numbers are the same as the Debian releases on which it’s based. So I’m running running Raspbian GNU/Linux 11 (bullseye) (now on arm64), which is based on Debian 11 (bullseye). After switching the Pi to arm64 and before I re-installed Jami , in lieu of instructions for Raspberry Pi OS I followed the instructions for Debian 11 (64-bit). This resulted in “Together” being installed. This came from the standard Raspberry Pi repositories, presumably because there wasn’t a candidate for arm64 in the Jami repository.
The information at Report a bug: chat view cannot show in debian installed from snap suggests that all I can do is report a bug with the snap installation. I’ve grabbed the messages it produced in order to do that. Edit: Maybe not.
apt installation is very much preferable to both snap and flatpack.
Thank you for translating the French how-to. I’ll attempt a bi-lingual diff to see if I can spot anything that doesn’t look right to me 
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