Edit File: wpdialog.js
/** * @output wp-includes/js/wpdialog.js */ /* * Wrap the jQuery UI Dialog open function remove focus from tinyMCE. */ ( function($) { $.widget('wp.wpdialog', $.ui.dialog, { open: function() { // Add beforeOpen event. if ( this.isOpen() || false === this._trigger('beforeOpen') ) { return; } // Open the dialog. this._super(); // WebKit leaves focus in the TinyMCE editor unless we shift focus. this.element.trigger('focus'); this._trigger('refresh'); } }); $.wp.wpdialog.prototype.options.closeOnEscape = false; })(jQuery);