[GUI] Comment bubble colour

I love the “tutorial” content that gets added to a new account; it’s been a great help as I try to get up to speed on how Mentat works.
The “I have a comment” HUD instructs the user to click the blue comment bubble to close it, but the comment bubble is green when it’s open, blue when it’s already closed.
http://skitch.com/justg/ghaj/mentatguicommentbu…