PHP warning: key “admin-site-enhancements/admin-site-enhancements.php” in

In admin plugins pages (wp-admin/plugins.php) i got many errors like this:

key "admin-site-enhancements/admin-site-enhancements.php" in /.../wordpress/wp-content/plugins/admin-site-enhancements/classes/class-admin-interface.php on line 1290

Warning: Trying to access array offset on null in /.../wordpress/wp-content/plugins/admin-site-enhancements/classes/class-admin-interface.php on line 1290

Quick fix is to add @ character on 1290 line.

            return @strcasecmp( $wp_list_table->items[$a]['Name'], $wp_list_table->items[$b]['Name'] );