WordPress在TinyMCE编辑器中注入自己的外部脚本文件iframe, 请参见示例wp-includes/js/tinymce/plugins/wpembed/plugin.js 文件：

(function ( tinymce ) {
    \'use strict\';

    tinymce.PluginManager.add( \'wpembed\', function ( editor, url ) {
        editor.on( \'init\', function () {
            var scriptId = editor.dom.uniqueId();

            var scriptElm = editor.dom.create( \'script\', {
                id: scriptId,
                type: \'text/javascript\',
                src: url + \'/../../../wp-embed.js\'
            } );

            editor.getDoc().getElementsByTagName( \'head\' )[ 0 ].appendChild( scriptElm );
        } );
    } );
})( window.tinymce );