Use Distrobox to containerise your desktop
https://blog.9wd.eu/posts/distrobox-assemble/
When I first heard about the Steam Deck I was keen to get my hands on one, and while I cannot claim to be a gamer, I do have a few games in my Steam library that I enjoy firing up on the sofa in the evenings. The Steam Deck also has a desktop mode, but as SteamOS is immutable by default, additional applications need to be installed via flatpak, which does not offer the same variety of applications as other distributions such as Ubuntu.
I saw yesterday that the current development version of Distrobox has gained the ability to define applications not only to the desktop launcher, but now also to the $PATH to invoke distrobox applications from the cli.
For those who have not yet heard of Distrobox, I wrote the linked blog explaining how I can now run a cli tool that I have already packaged for a ci pipeline in a Distrobox on my Steam deck.