The emoticon-button for etmoticons displays as the link icon, and the link icon is a tool. I managed to get my smiley icon back in Chrome by cmd + shift + r a lot of times.
 

This is how a lot of users sees it:


This is how I see it after force refreshing ~10 times (in ACP):

 

Both toolbars is exactly the same (no edits are made in ACP).

V4.1.1

Clear your browser cache. 

40 minutes ago, CA3LE said:

Clear your browser cache. 

Thanks, I had the same issue but after clearing all caches (not just refreshing the site without cache) everything is working again! :)

Deleting Safari cache solved the problem, thanks! Sorry for not testing this before posting.

I had the same error and simply changed the default editor....