Decky Loader: had to manually add ~/.steam/steam/.cef-enable-remote-debugging to get UI to load.

[knokelmaat]

It took me some time to figure out why Decky Loader wasn't showing up in SteamOS UI after enabling the option jovian.decky-loader.enable.

Finally by looking at the default install script (https://github.com/SteamDeckHomebrew/decky-installer/blob/main/cli/install_release.sh), I saw that CEF remote debugging needs to be enabled. The install script does this automatically, but the option jovian.decky-loader.enable in Jovian-NixOS does not.

Is it possible to add this functionality automatically or to add this info to the documentation? My apologies if this is a mistake on my part, I'm still quite new to nix (been using it for less than a year).

[K900]

This is a known issue. We can't enable CEF debugging automatically, because we can't disable it after - the file being removed does not lead to it being disabled in Steam, and it is a potential attack vector. The documentation should probably mention that you need to enable it manually though.

[samueldr]

Known workaround

Since it's not possible to disable CEF debugging, which should be seen as a possible (but low) vulnerability vector^{[citation needed]}, we can't enable CEF debugging at this point within the Jovian NixOS options without making things awkward for end-users who want it enabled without enabling decky-loader.

For now, the easiest way forward is to login as the user running Steam on your system, and run the following:

 $ touch ~/.steam/steam/.cef-enable-remote-debugging

See: https://github.com/SteamDeckHomebrew/decky-loader/blob/6993516ccb8b371a0b1c8152a3c672fffffad7dc/dist/install_release.sh#L14

There is also a developer mode option in the Steam interface to enable/disable this option.

(This comment is linked from the documentation.)