When I go to my friends list and press "Join" to join one of my friends, I see:

"We apologize for the inconvenience, but this button is temporarily disabled. You can join your friend through the Join Game screen screen in the World Map. Filter for your friend's name. This will be fixed asap."

OK, fine. My question is about the "Filter for your friends name" part. Is this possible? The only filters I see on the join game screen are:

<Game Name>
<Min Level>
<Max Level>
<Campaign>

Where would I put my friends name on this screen?

(I'm using Android.)