Me and my friend were in a public world hanging out and I created a friends+ intending to invite him once I loaded in.

When I loaded in, I was not able to invite him. The invite button and request invite buttons were missing entirely.

I noticed the world still said 2/8 people in it, when it should've been 1/8 when I left.

As soon as he changed worlds on his own, the invite buttons appeared instantly.

I think the game didn't update and still thought I was in the same world as him, and therefore wasn't showing the invite buttons. When I had been in a new world for over 5 minutes.

So I guess the bug is, the menu doesn't always register when you change worlds and people in your old world, you cannot send invites to or request invite.