Issue #3265121 by andypost, longwave, Spokje, neclimdul, smustgrave: Remove...

<?php

namespace Drupal\Core\Http;

@trigger_error('The ' . __NAMESPACE__ . '\RequestStack is deprecated in drupal:10.0.0 and is removed from drupal:11.0.0. There is no replacement. See https://www.drupal.org/node/3265357', E_USER_DEPRECATED);

use Symfony\Component\HttpFoundation\Request;

use Symfony\Component\HttpFoundation\RequestStack as SymfonyRequestStack;

/**

 * Forward-compatibility shim for Symfony's RequestStack.

 *

 * @deprecated in drupal:10.0.0 and is removed from drupal:11.0.0. There is no

 *   replacement.

 *

 * @see https://www.drupal.org/node/3265357

 *

 * @todo Remove this in Drupal 11 https://www.drupal.org/node/3265121

 */

class RequestStack extends SymfonyRequestStack {

  /**

   * Gets the main request.

   *

   * @return \Symfony\Component\HttpFoundation\Request|null

   *   The main request.

   */

  public function getMainRequest(): ?Request {

    @trigger_error('The ' . __NAMESPACE__ . '\RequestStack is deprecated in drupal:10.0.0 and is removed from drupal:11.0.0. There is no replacement. See https://www.drupal.org/node/3265357', E_USER_DEPRECATED);

    return parent::getMainRequest();

  }

}

<?php

declare(strict_types=1);

namespace Drupal\Tests\Core\Http;

use Drupal\Core\Http\RequestStack;

use Drupal\Tests\UnitTestCase;

/**

 * @coversDefaultClass \Drupal\Core\Http\RequestStack

 * @group legacy

 *

 * @todo Remove this in Drupal 11 https://www.drupal.org/node/3265121

 */

class RequestStackLegacyTest extends UnitTestCase {

  /**

   * Tests deprecation message in our subclassed RequestStack.

   *

   * @covers ::getMainRequest

   */

  public function testGetMainRequestDeprecation() {

    $stack = new RequestStack();

    $this->expectDeprecation('The Drupal\Core\Http\RequestStack is deprecated in drupal:10.0.0 and is removed from drupal:11.0.0. There is no replacement. See https://www.drupal.org/node/3265357');

    $this->assertNull($stack->getMainRequest());

  }

}