@marat.agl

Thanks for the patch @joseph.olstad
I also encountered this problem and solved the issue in this way, since for me the output of more than 10,000 menu items was not of great importance, I limited the depth to level 2 (setMaxDepth), thereby I achieved normal operation of editing and creating a page, and I edit the menu through the bigmenu module .

Sample:

 $route = \Drupal::routeMatch()->getRouteName();
 if ($route == 'entity.node.edit_form' || $route == 'node.add' ) {
     // my big menu (10000 links)
     if ($menu_name='menu-menu-category' ) {
          $parameters->onlyEnabledLinks();
          $parameters->setMaxDepth(2);
    }
    }

Thanks for the patch @joseph.olstad
I also encountered this problem and solved the issue in this way, since for me the output of more than 10,000 menu items was not of great importance, I limited the depth to level 2 (setMaxDepth), thereby I achieved normal operation of editing and creating a page, and I edit the menu through the bigmenu module .

Sample:

 $route = \Drupal::routeMatch()->getRouteName();
    if ($route == 'entity.node.edit_form' || $route == 'node.add' ) {
        // my big menu (10000 links)
        if ($menu_name='menu-menu-category' ) {
            $parameters->onlyEnabledLinks();
            $parameters->setMaxDepth(2);
    }
    }