diff -u b/core/modules/menu_link_content/src/Form/MenuLinkContentForm.php b/core/modules/menu_link_content/src/Form/MenuLinkContentForm.php
--- b/core/modules/menu_link_content/src/Form/MenuLinkContentForm.php
+++ b/core/modules/menu_link_content/src/Form/MenuLinkContentForm.php
@@ -274,6 +274,8 @@
     $entity->enabled->value = (bool) $new_definition['enabled'];
     $entity->expanded->value = $new_definition['expanded'];
 
+    $entity->link->uri = $form_state->getValue('url');
+
     return $entity;
   }
 
diff -u b/core/modules/menu_link_content/src/MenuLinkContentAccessControlHandler.php b/core/modules/menu_link_content/src/MenuLinkContentAccessControlHandler.php
--- b/core/modules/menu_link_content/src/MenuLinkContentAccessControlHandler.php
+++ b/core/modules/menu_link_content/src/MenuLinkContentAccessControlHandler.php
@@ -65,7 +65,7 @@
           // If there is a URL, this is an external link so always accessible.
           $access = AccessResult::allowed()->cachePerRole()->cacheUntilEntityChanges($entity);
           /** @var \Drupal\menu_link_content\MenuLinkContentInterface $entity */
-          if ($entity->getUrlObject()->isRouted()) {
+          if (!$entity->getUrlObject()->isRouted()) {
             $url_object = $entity->getUrlObject();
             // We allow access, but only if the link is accessible as well.
             if ($url_object->isRouted()) {