Enable Theme and Plugin Editor on Wordpress MU

If you have installed Wordpress MU and like to have the theme editor and plugin editor for easy customization of themes and plugin from dashboard (like normal wordpress), then here is the customization technique to get the same. For those who are new to Wordpress MU, there is no provision for tabs as “Theme Editor” under Appearance section and “Plugin Editor” under Plugins section on Dashboard in WPMU.

To get the theme editor panel in WPMU, follow the below steps,

Edit MU.PHP file

To get the editor on dashboard, you will have to edit the mu.php file available under “wp-admin/includes” folder of your Wordpress MU installation.

1. Search for the term “unset( $submenu['themes.php'][10]” in mu.php, you will find only one search result. At that place, you ned to make changes. We have provided below the before and after changes code. We need to comment two lines which are actually there to remove plugin editor and theme editor.

Before Changes

unset( $submenu['plugins.php'][15] ); // always remove the plugin editor
unset( $submenu['themes.php'][10] );  // always remove the themes editor

After Changes

/* unset( $submenu['plugins.php'][15] ); */ // always remove the plugin
/* unset( $submenu['themes.php'][10] ); */ // always remove the themes

2. After removing this check, you should be able to see the theme editor and plugin editor option but still those pages will not accessible. To remove that barrier, you need to make below changes in mu.php only.

Search for the term “if ( strpos( $_SERVER['PHP_SELF'], ‘user-new.php’” in mu.php and then see below the before and after code for the same line (search result)

Before Changes

$pages = array( 'theme-editor.php', 'plugin-editor.php' );
foreach( $pages as $page ) {
    if ( strpos( $_SERVER['PHP_SELF'], $page ) ) {
        wp_die( __('Page disabled by the administrator') );

After Changes

$pages = array( 'theme-editor.php', 'plugin-editor.php' );
  foreach( $pages as $page ) {
     if ( strpos( $_SERVER['PHP_SELF'], $page )&& !is_site_admin() ) {
         wp_die( __('Page disabled by the administrator') );

Now you can check in your Wordpress MU dashboard; the theme editor and plugin editor should work properly in your MU installation.

Note: if you are using Wordpress MU 2.7 or below that then you will have to copy theme-editor.php from normal wordpress setup (wp-admin/theme-editor.php) to the same location in WPMU. After WPMU 2.7, Wordpress started giving theme-editor.php with the installation setup.

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