diff -u b/src/Controller/OpenIDConnectRedirectController.php b/src/Controller/OpenIDConnectRedirectController.php
--- b/src/Controller/OpenIDConnectRedirectController.php
+++ b/src/Controller/OpenIDConnectRedirectController.php
@@ -349,7 +349,7 @@
    * @return \Drupal\openid_connect\Plugin\OpenIDConnectClientInterface|null
    *   The client plugin begin called or NULL if none are available.
    */
-  private function getClient(string $client_name): ?OpenIDConnectClientInterface {
+  protected function getClient(string $client_name): ?OpenIDConnectClientInterface {
     $configuration = $this->config('openid_connect.settings.' . $client_name)
       ->get('settings');
 
diff -u b/src/OpenIDConnectSession.php b/src/OpenIDConnectSession.php
--- b/src/OpenIDConnectSession.php
+++ b/src/OpenIDConnectSession.php
@@ -64,7 +64,8 @@
       // Make sure the uri is not external.
       if (!$target_link_uri->isExternal()) {
         // This path is internal.
-        $path = $target_link_uri->toString();
+        $target_path = $target_link_uri->toString(TRUE);
+        $path = $target_path->getGeneratedUrl();
         $query = $target_link_uri->getRouteParameters();
       }
     }