Firefox 50's release notes:
Emoji for everyone! Firefox will use built-in Emoji on operating systems without native Emoji fonts (Windows 8.0 and lower and Linux)
So I'm on Windows 7 and I absolutely dislike colored emoji for how much distracting they are. There is no font file called "EmojiOne Mozilla" to delete from Windows' fonts folder, unfortunately. And there is no relevant option in
about:config list I could find.
How do I disable colored emoticons?