I personally do a mixture of both!
Joining role-plays is fun because you can directly be placed with people who have similar things in common to you, [aggressive rps, passive rps, mapped rps, nonmapped, depends on the group!] But, not all role-plays are active and some will die out.
On the chit-chat side of things I like to talk about what's going on and what's currently happening. Most likely relatable topics and noncontroversial things. I myself, have trouble talking to others so I just post something random in chat like: 'That moment when you realize, you forgot to add a marking on your character's preset after you exported it.' Something like that, most likely starting with 'That moment when'.. I'm that person. lol.
But overall, yea, that's just what I do.. cx