The commenter talking about xdg desktop portal is correct for the file picker; you need to install a portal for that.
I can’t get links to open from discord
Are you using dbus? Display managers normally will launch graphical sessions with dbus for you, but if you’re manually launching from the tty, use dbus-run-session sway (or the name of the executable you want to run). dbus is used for applications to communicate with each other, e.g. Discord to communicate with your browser. And you need dbus installed and the daemon running, of course.



Not sure what ly is but basically I’m saying you should be using the
dbus-run-session swaycommand to run sway instead of justsway. If dbus is installed and the daemon is running then this will allow you to e.g. open links in Discord.