"Editor to use" dropdown appears to be gone

I’ve built a couple of sites with MODx 0.9.6 (and earlier). Wherever TinyMCE was used, below the textarea there used to be a dropdown that said "Editor to use" where one could choose between TinyMCE and "none".
Now for a new site I’ve upgraded from 0.9.6 to 1.0.3, I’ve done some tweaking and suddenly I find this dropdown has gone. And I miss it. Sometimes I need to work directly with the html instead of TinyMCE.
Any ideas how restore it? I couldn’t find anything in the TinyMCE settings and the manager configuration. Help would be greatly appreciated!

I’m using TinyMCE version 3.3.2.

It’s still there in the fresh install so the first thing I would do is re - upload all the tinymce files to /public_html/assets/plugins/ *tinymce-folder*

Thanks for your help!
Unfortunately it didn’t work
I’ve done some more research and found out the problem appears to be related to YAMS. So I’ll bring it up in the YAMS subforum.