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It seems all windows (logs, squash commits etc) can show Emojis (if the message already has them and I’m not referring to text emojis like :bug: - rather emoji fonts that you can insert using Win+. or Ctrl+Cmd+Space on Mac).

Only the commit message window doesn’t let you enter them on Mac - Ctrl+Cmd+Space doesn’t bring up the Character Viewer. Almost every other Git Client on the planet supports this. 

I'm guessing SmartGit uses non-native controls or does something funky to restrict them. 

So if supporting GitMojis is low priority, maybe you can at least fix the Mac bug? That'll probably help a lot.