Howdy,
I'm trying to create a search filter that allows me to show comments which have tagged the current user, plus a special character as a flag. The purpose of this is to make a "Comments Requiring Replies" filter.
In a task I'd like users to be able to tag another user and add an exclamation mark (or other character) after tagging the user so that it can be marked as needing attention/needing a reply.
For example:

I'm not married to this exact method at all, I really just need a way to show a logged in user that there's a comment on a task, and they need to reply / pay attention to it before the task can move forward.
The JQL I've attempted to use is based on the search "comment ~ currentUser()" which does work, but figuring out how to add the operator in there is proving really friggin difficult.
So far I've tried:
comment ~ currentUser()!
comment ~ "currentUser()!"
comment ~ (currentUser()!)
comment ~ "currentUser()!"
and every other combination of spaces, quotes, brackets and prayer to ancient deities that I could come up with. Any advice is greatly appreciated.