CKEditor placeholder text doesn't work (config.js)
I'm assuming you are using wysiwyg with ckeditor.

The problem is that wysiwyg pass the configuration to the editor, in our case ckeditor, based on the options selected on the wysiwyg profile in use.

The solution i found sure it's not the best buts works for me. It's about modifying the wysiwyg file thats sets the configuration for ckeditor.

Open site/all/modules/wysiwyg/editors/ckeditor.inc and find the function wysiwyg_ckeditor_settings, then, before the code implode the $extra_plugins array add your extra plugins.

before:

if (!empty($extra_plugins)) {
  $settings['extraPlugins'] = implode(',', $extra_plugins);
}


add:

$extra_plugins[] = 'confighelper';


result:

$extra_plugins[] = 'confighelper';
if (!empty($extra_plugins)) {
  $settings['extraPlugins'] = implode(',', $extra_plugins);
}


Hope it helps.