No Editing toolbar...
Console throws an error when the edit pop-up opens:
Uncaught TypeError: Cannot read property 'form' of null
Open the web developer toolbar in your browser.
I had something similiar during update form 5.6.2.x to 188.8.131.52.
The browser tried to request a language specific file for the tinymce (the editor).
In the console I saw a 404 for
I copied the "en.js" in that dir to "de.js" and it worked.
Thanks, but in my case the (Dutch) language file is being loaded correctly (status 200). Just to make sure it doesn't have anything to do with languages I changed the user's language back to English US and still I'm getting the same error in the console and is the WYSIWYG editor not showing up.