I've noticed this recently but unlike in the message box and all why can't you use emoticons/emojis on Message/Thread Titles I tried the 
and it doesn't show as a heart is this a bug or just not implemented yet?
and it doesn't show as a heart is this a bug or just not implemented yet?
I don't think it's a bug and works as intended, but you can always send a bug report to Kim and verify that. 
The emojis are added as part of processing all BBCode tags. As I don't want to allow bold, italic, collapse tags or really any other form of styling in forum titles, I don't do any BBcode processing on titles. Thus, the emojis are also not processed.
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