Once again, doing a bit of archiving for future reference. Planning to try to get a Steam Deck this summer; Jellyfin set-up continues to move slowly.
- while you’re at it, launch it and set up your server
- right click on JMP in the application menu and “Add to Steam” optional: for improved controller support, install and open Flatseal and add “/run/udev:ro” (without quotes) under filesystem -> other files for JMP go back to Game Mode optional: use Decky and the SteamGridDB plugin to make it look pretty (there are plenty of community assets to choose from already, so this is time well spent) if you haven’t granted controller access above, select controller settings and download and apply the most popular layout click “Play” Open the client settings inside JMP and enable “Fullscreen” (might have to force the screen if Auto doesn’t work) that’s it, enjoy
Sourced from this comment on an r/SteamDeck post