Steps to reproduce:

  1. Set admin theme to something other than the default (main) theme
  2. Go to /admin/config/content/ckeditor/edit/Full
  3. The theme path in the CSS fieldset will display the admin theme's path, even though in, line 740, we are using variable_get('theme_default', $theme); which will pull from the default theme.

The attached patch fixes this.



Patch attached