Rather than just Fennec, the FFUpdater app will pull a number of Mozilla applications and keep them current. The list appears to be: Focus, Klar, Lockwise, Beta

Rather than just Fennec, the FFUpdater app will pull a number of Mozilla applications and keep them current. The list appears to be: Focus, Klar, Lockwise, Beta & Nightly, plus Iceraven, Brave and Vivaldi, and an unGoogled Chromium. It also seems to want to maintain my Bromite.