For example, on Messages.app, the sidebar with recent contact list displays Emojis but the message pane does not:
How do I fix this short of reinstalling Mac OS?
I'm on MacOS Mojave 10.14.2 (18C54). I believe it started happening since update to 10.14.1.
I've tried the Font Book > Restore Standard Fonts..., validated the fonts but not luck.
Firefox displays emojis fine.