I too, am having the same issue. It’s only with this install – all of my other installations are fine. I have tried everything that I could think of and everything that has been recommended.
I even tried re-installing previous version (2.5), with no success. Hope there’s a solution soon.
I’m having the same problem. I upgraded yesterday, made one simple adjustment and then “POOF!” The editor was gone.
I disabled all plugins; I reinstalled a clean editor; I tried installing the older editor (which happens to work on one of my other sites with no problem); I ultimately had to find a plugin, which does the trick, but I would prefer that the packaged one worked. *sigh*
