diff --git a/core/modules/outside_in/src/OffCanvasFormDialogTrait.php b/core/modules/outside_in/src/OffCanvasFormDialogTrait.php
index 990d897e4f..00954fb308 100644
--- a/core/modules/outside_in/src/OffCanvasFormDialogTrait.php
+++ b/core/modules/outside_in/src/OffCanvasFormDialogTrait.php
@@ -5,7 +5,6 @@
 use Drupal\Core\Ajax\AjaxResponse;
 use Drupal\Core\Ajax\RedirectCommand;
 use Drupal\Core\Ajax\ReplaceCommand;
-use Drupal\Core\EventSubscriber\MainContentViewSubscriber;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Url;
 
@@ -22,18 +21,6 @@
 trait OffCanvasFormDialogTrait {
 
   /**
-   * Determines if the current request is for an AJAX modal dialog.
-   *
-   * @return bool
-   *   TRUE is the current request if for an AJAX modal dialog.
-   */
-  protected function isOffCanvasDialog() {
-    $wrapper_format = $this->getRequest()
-      ->get(MainContentViewSubscriber::WRAPPER_FORMAT);
-    return $wrapper_format === 'drupal_dialog.off_canvas';
-  }
-
-  /**
    * Adds modal dialog support to a form.
    *
    * @param array $form
@@ -42,13 +29,7 @@ protected function isOffCanvasDialog() {
    *   The current state of the form.
    */
   protected function buildFormDialog(array &$form, FormStateInterface $form_state) {
-    if (!$this->isOffCanvasDialog()) {
-      return;
-    }
-
     $form['actions']['submit']['#ajax'] = [
-      'dialogType' => $this->getDialogType(),
-      'dialogRenderer' => $this->getDialogRenderer(),
       'callback' => '::submitFormDialog',
       'event' => 'click',
     ];
@@ -58,33 +39,6 @@ protected function buildFormDialog(array &$form, FormStateInterface $form_state)
   }
 
   /**
-   * @return mixed
-   */
-  protected function getRequestWrapperFormat() {
-    $wrapper_format = $this->getRequest()
-      ->get(MainContentViewSubscriber::WRAPPER_FORMAT);
-    return $wrapper_format;
-  }
-  /**
-   *
-   */
-  protected function getDialogType() {
-    $wrapper_format = $this->getRequestWrapperFormat();
-    $wrapper_format_parts = explode('.', $wrapper_format);
-    // Remove the "drupal_" prefix.
-    return substr($wrapper_format_parts[0], 7);
-  }
-
-  /**
-   *
-   */
-  protected function getDialogRenderer() {
-    $wrapper_format = $this->getRequestWrapperFormat();
-    $wrapper_format_parts = explode('.', $wrapper_format);
-    return isset($wrapper_format_parts[1]) ? $wrapper_format_parts[1] : NULL;
-  }
-
-  /**
    * Submit form dialog #ajax callback.
    *
    * @param array $form