Rebuilding menu tree?

It's just occurred to me why this isn't working. So I'll close this issue.

Reopening this as I'm running into a new similar/related issue. When programmatically creating menu links that will live in a different menu entirely, I keep finding that menu_tree gets updated with group_menu_link_content-1 rather than the menu name that I've specified.

I've been creating my menu link as follows. The node is a node that belongs to a group so wonder if something is post processing the menu link creation to assign the link to a different menu? Oddly, if I look at menu_link_content, I can see the correct group has been stored in menu_name, it's just in menu_tree where it differs.

      $menu_link = \Drupal::entityTypeManager()
        ->getStorage('menu_link_content')
        ->create([
          'title' => $definition['title'],
          'description' => $definition['description'],
          'link' => [
            'uri' => 'entity:node/' . $definition['route_parameters']['node'],
          ],
          'menu_name' => $menu_name,
          'weight' => $definition['weight'],
          'enabled' => boolval($definition['enabled']) ? TRUE : FALSE,
          'expanded' => boolval($definition['expanded']) ? TRUE : FALSE,
          'parent' => $definition['id'] !== $parent_menu_link['id'] ? $parent_menu_link['id'] : NULL,
        ]);
      $menu_link->save();

Ok, closing this (again) :) It looks like it's something in MenuTreeStorage which is causing this issue and I think I've found a work around.