PHP errors when adding new sites

I’m experiencing the same issue as explained here when creating new sites:

https://ww.wp.xz.cn/support/topic/php-errors-when-adding-new-sites?replies=6

But that topic is closed to replies so I’m creating a new one.

The issue occurs when you have no plugins set to auto-activate.

This can be fixed with the following patch:

Index: wp-content/plugins/multisite-plugin-manager/plugin-manager.php
===================================================================
--- wp-content/plugins/multisite-plugin-manager/plugin-manager.php      (revision 4036)
+++ wp-content/plugins/multisite-plugin-manager/plugin-manager.php      (working copy)
@@ -294,7 +294,7 @@
          require_once( ABSPATH.'wp-admin/includes/plugin.php' );

                $auto_activate = (array)get_site_option('pm_auto_activate_list');
-               if (count($auto_activate)) {
+               if (count($auto_activate) && $auto_activate[0] != 'EMPTY') {
                switch_to_blog($blog_id);
            activate_plugins($auto_activate, '', false); //silently activate any plugins
            restore_current_blog();

https://ww.wp.xz.cn/plugins/multisite-plugin-manager/