how to make cider work on steam deck in game mode? when I add cider as a game on steam it just won't start

I just installed it.

1. In desktop mode, open itch.io, install the flatpack version of Cider. (Use the gear icon to select which installation.)
2. Launch from itch.io, then run the flatpack file it opens, that will open up the program in Discover. Install that.
3. Now search for Cider in your programs, and select add to Steam.
4. Be sure to sign in to Apple Music while you are in desktop mode.
5. You can use the Steam Grid DB decky plugin to add artwork and logos to it if you like keeping your library pretty.