There was a thread here with a good terminal one liner to get steam to “Iconify” to tray when Closed/Minimised.
It modify’s a line in the /usr/bin/steam file from:
export STEAM_FRAME_FORCE_CLOSE=0 to: export STEAM_FRAME_FORCE_CLOSE=1
Every time manjaro applications update it resets that file to its =0 state.
I was hoping someone here remembers the command used and could share that with me