diff --git a/wp-admin/includes/class-wp-upgrader.php b/wp-admin/includes/class-wp-upgrader.php
index fe2d67f0d..177989255 100644
--- a/wp-admin/includes/class-wp-upgrader.php
+++ b/wp-admin/includes/class-wp-upgrader.php
@@ -1520,7 +1520,7 @@ class Theme_Installer_Skin extends WP_Upgrader_Skin {
$install_actions = array();
$install_actions['preview'] = '' . __('Preview') . '';
- $install_actions['preview'] .= '' . __('Customize') . '';
$install_actions['activate'] = '' . __('Activate') . '';
if ( is_network_admin() && current_user_can( 'manage_network_themes' ) )