Valve has shipped various fixes in an updated Steam Deck Client to the Stable channel which you can find below.
General
When reconnecting to Steam (including when resuming from suspend), in game notifications will no longer appear for friends currently in a game.
Fixed an error when accessing notes.
Fixed an error when receiving a voice chat invite.
Fixed default start-up animation when docked.
Desktop Mode
Fixed the refresh button on the server browser dialog needing to be scrolled into view.
Fixed the Backup Game Files dialog sometimes failing to complete.
Steam Input
Fixed L3/R3 buttons not working on fight sticks or other devices that don't have left/right stick analogue axes.