Common config options for ckeditor.

thejibe_ckeditor_custom_config.js

/**
 * @file thejibe_ckeditor_custom_config.js
 * Includes custom js config - http://docs.ckeditor.com/#!/api/CKEDITOR.config
 */

CKEDITOR.editorConfig = function( config )
{

  // Preserve class formatting.
  config.allowedContent = true;

  // Don't add   to empty elements
  config.fillEmptyBlocks = false;

}

/**
 * Set link button to have a default setting of _blank.
 */
// Register a placeholder plugin so CKEditor won't complain.
CKEDITOR.plugins.add('default_target', {
  requires: ['link'],
  init: function(editor) {
  }
});

// Hook into dialog creation to set our override.
CKEDITOR.on('dialogDefinition', function(ev) {
  var dialogName = ev.data.name, dialogDefinition = ev.data.definition;
  if (dialogName == 'link') {
    var targetTab = dialogDefinition.getContents('target');
    var targetField = targetTab.get('linkTargetType');
    targetField['default'] = ev.editor.config.DefaultLinkTarget;
    var oldSetup = targetField.setup;
    targetField.setup = function(data) {
      targetField.onChange.call(this);
      if (oldSetup) {
        oldSetup.call(this, data);
      }
    }
  }
});

// Sets the default config value to _blank.
CKEDITOR.config.DefaultLinkTarget = '_blank';