My instance (Discourse 2.2.1) is set to allow a max of 1 emoji in a topic title (default setting):
However, it seems that users can use multiple custom emoji in topic titles despite that setting:

My instance (Discourse 2.2.1) is set to allow a max of 1 emoji in a topic title (default setting):
However, it seems that users can use multiple custom emoji in topic titles despite that setting:

I see, yeah we should fix that … @techAPJ can you add to your list?
Add as very low priority to your list 
Hey, I have created a PR addressing this issue 
Sadly, I can’t – our forum is on the stable branch, and I don’t currently have a test version set up anywhere. Maybe someone who’s on the beta branch could give it a try?
I confirmed the fix locally by testing before and after the commit. 