Today one of my clients called me with this problem:
When I click article manager or category manager in order to edit an article or category, I see a page with no textarea, no buttons, no menus
Was a weird call, and proven to be a difficult problem
I checked his page (Joomla 2.5 with JCE editor) and at first sight I didn't see anything obviously broken, beside the article editor behaving indeed weird, showing a few lines of unformatted form (the form elements above the text editing area). I suspected that JCE was broken somehow, and I switched immediately to TinyMCE - then to No editor mode, but the problem persisted.
Not even unistalling and reinstalling JCE does not helped. Then remembered a similar incident few months ago, then I experienced with this site something similar - the modules where uses a text editor areas behaved similarly.
BINGO! Was a correct guess - and an easy fix from there. There are big chances that the problem is generated by one of faulty plugins. Not ANY plugi, but one of extended editor plugins. Back then the culprit was the "Attachment" plugin, but since there that plugin wasn't installed, must be another one.
You have at least 2 solutions from there.
a. The geeky solution
In Joomla main cnfiguration set the error level to Maximum or Developer levels and open the article editor. The clue will be the last error shown on that page - usually a PHP Fatal Error
b. The Trial and Error solution
Go to Plugin manager, filter for the "editors-xtd plugin type and disable the plugins one at time and check when the editor comes back to life.
This time the culprit was the Autosave plugin which does not "survived" the recent PHP version update on the server.
The weird thing is, that searching the net does not revealed anything close to this. Until now !