Most importantly - we're here for you! Please let us know via in-app help if you're having any trouble with Tandem on Linux.
Tandem is distributed via .deb and .rpm packages as well as via Canonical's Snap Store. The only difference is that Snaps run in a special sandbox that requires an extra step to set up camera and audio permissions.
Any updates to Tandem will be shown in-app, where users can download the latest package from our download page. If you are trying to migrate from a Snap to a .deb or .rpm (or vice versa), you will have to first uninstall the other version of Tandem, otherwise they will both show up on your desktop.
If you're using the Snap store, snaps run in a sandbox and require an additional step to connect extra abilities. If you installed Tandem from the Snap store, there should be a Permissions button on the Tandem page that lets you add camera / audio permissions. Or, run the following:
sudo snap connect tandem:camera :camera sudo snap connect tandem:audio-record :audio-record sudo snap connect tandem:pulseaudio :pulseaudio
If that didn't help, or you aren't using the Snap store, check your system settings app to make sure that the audio input device is configured and turned on.
In addition, some machines may require a reboot before permissions are fully activated.
Another thing you can check is whether your user has been added to the "audio" group, which is required on Pulseaudio to access certain devices:
sudo usermod -a -G audio peter
Unfortunately, there are no standard APIs available on Linux for interfacing with Chrome and Firefox. You will have to install a browser extension. Tandem does not endorse these third-party extensions, but will work with the format they output, which is adding the URL (including http://) to the window title.