In Joomla 3.3.6 and 3.3.7 the Plugin "Button - Article" (plugin type: editors-xtd) is protected and cannot be unpublished.

Steps to reproduce the issue

Install Joomla 3.3.6 or 3.3.7,
Go to Extensions > Extension Manager > Manage
Search for editor-xtd plugins (Filter: Type = plugin, Folder = editors-xtd)
It will show 4 editor-xtd plugins, the "Button - Article" plugin is marked as "protected".

Expected result

I use JCE editor and from usability point of view, would like to unpublish all unused buttons that are displayed below the editor. In previous versions I was able to unpublish all 4 "Buttons".

Actual result

All buttons, except the "Button - Article", can be unpublished.
The "Button - Article" is marked as protected.

System information (as much as possible)

Additional comments

I'll add a patch...