(Spoilers for the final boss, just in case)

!The corpse is Radagon and the amoeba is Elden Beast!<

UFW, by default, blocks all incoming requests. This means that SSH (port 22) is blocked already. Then, if you need to, whitelist (ALLOW) ports that you want to expose to the network. For example, I have ports 1714-1764 whitelisted for KDE Connect and everything else is blocked.

I suspect you have installed either Lutris or Steam through flatpak.

Try installing both using the same method or install MangoHud both as a flatpak and a system package.

Also, I recommend enabling MangoHud with ‘MANGOHUD=1 %command%’ instead.

This video is almost three months old, why post now?