Ticket #57205: 57205.diff

src/wp-includes/class-wp-hook.php

@@ -74 +74 @@
         public function add_filter( $hook_name, $callback, $priority, $accepted_args ) {
                 $idx = _wp_filter_build_unique_id( $hook_name, $callback, $priority );
 
+                if ( ! is_int( $priority ) ) {
+                        $priority = (string) $priority;
+                }
+
                 $priority_existed = isset( $this->callbacks[ $priority ] );
 
                 $this->callbacks[ $priority ][ $idx ] = array(