@mention of users stalls on Loading... in fresh install of Vanilla 3.3
I have setup a new Vanilla 3.3 forum (my host doesn't support MySQL 5.7 so Vanilla 3.3 is my only option) and for some reason, when I try to @ mention a user it just gets stuck on "Loading..." and nothing ever comes up.
It works just fine on another Vanilla forum that I setup a few months ago so I know it's not my browser or script blocking. It seems to be a fault in this new installation.
Any suggestions or advice on how to troubleshoot or resolve this?