Passing parameters to Flatpak app

Hi Everyone,

On non-flatpak version of Signal I am able to pass “–use-tray-icon” by editing the shortcut so the app keeps running in the background.

I have tried to do this with flatpak version of Signal, but I can’t seem to find where to add the launch paramter. The shortcut looks like this
“/usr/bin/flatpak run --branch=stable --arch=x86_64 --command=signal --file-forwarding org.signal.Signal @@u %U @@”

Can anybody advise?