I'm seeing this same issue but not using any multi-language plugins.  I'm missing the code, source code, and emoji buttons.  The utility works (you can add an emoji) but the interface is confusing people.  See the attached screenshot.  Is there a fix for this?  Thanks!

This is not an Emoji issue, this is TiniMCE toolbar icon issue. For some reason the editor toolbar addons are not loaded on your forum. Tr to disable all other plugins, delete all cache and check on other browsers and devices.

Then after tested many times,  I found that, no matter which Multi-language plugin I installed, user only can see the " Source Code Icon" on editor tool-bar,  when they are selected the language same as our Website Default Language. 

We just registered and checked the editor tool-bar. Unfortunately we could not find any reason why the source ( {:} )  button doesn't exists. This maybe a plugin or theme conflict. That's very hard to debug.

Thanks Robert for the help,

Yes, it is not bug, it is conflict with one plugin called - qTranslate-X

After disabled this plugin, I can see the Source Code Icon appears again  on editor tool-bar of the forum.

This one

https://www.iamguitarplayer.com/hk/community

Please leave some URL to allow us check it too.

but his problem is still occurs, attached please see the screen capture.

Anyone know what is the reason? 

Thanks in Advance.