在functions.php文件里添加一下代码即可：
//wp编辑器增强版
function add_editor_buttons($buttons) {
$buttons[] = 'fontselect';
$buttons[] = 'fontsizeselect';
$buttons[] = 'backcolor';
$buttons[] = 'underline';
$buttons[] = 'hr';
$buttons[] = 'sub';
$buttons[] = 'sup';
$buttons[] = 'cut';
$buttons[] = 'copy';
$buttons[] = 'paste';
$buttons[] = 'cleanup';
$buttons[] = 'wp_page';
$buttons[] = 'newdocument';
return $buttons;
}
add_filter("mce_buttons_3", "add_editor_buttons");