AfterPageTreeItemsPreparedEvent¶

services:
  # Place here the default dependency injection configuration

  MyVendor\MyExtension\Backend\EventListener\MyEventListener:
    tags:
      - name: event.listener
        identifier: 'my-extension/backend/modify-page-tree-items'

<?php

declare(strict_types=1);

namespace MyVendor\MyExtension\Backend\EventListener;

use TYPO3\CMS\Backend\Controller\Event\AfterPageTreeItemsPreparedEvent;

final class MyEventListener
{
    public function __invoke(AfterPageTreeItemsPreparedEvent $event): void
    {
        $items = $event->getItems();
        foreach ($items as $item) {
            // Set special icon for page with ID 123
            if ($item['_page']['uid'] === 123) {
                $item['icon'] = 'my-special-icon';
            }
        }
        $event->setItems($items);
    }
}