diff --git a/lib/private/Notification/Notification.php b/lib/private/Notification/Notification.php
index ff3826047d..ef7cdb5d44 100644
--- a/lib/private/Notification/Notification.php
+++ b/lib/private/Notification/Notification.php
@@ -1,5 +1,4 @@
 <?php
-declare (strict_types = 1);
 /**
  * @copyright Copyright (c) 2016, ownCloud, Inc.
  *
@@ -134,7 +133,7 @@ class Notification implements INotification {
 	 * @throws \InvalidArgumentException if the app id is invalid
 	 * @since 8.2.0
 	 */
-	public function setApp(string $app) {
+	public function setApp($app) {
 		if (!is_string($app) || $app === '' || isset($app[32])) {
 			throw new \InvalidArgumentException('The given app name is invalid');
 		}
@@ -156,7 +155,7 @@ class Notification implements INotification {
 	 * @throws \InvalidArgumentException if the user id is invalid
 	 * @since 8.2.0
 	 */
-	public function setUser(string $user) {
+	public function setUser($user) {
 		if (!is_string($user) || $user === '' || isset($user[64])) {
 			throw new \InvalidArgumentException('The given user id is invalid');
 		}
diff --git a/lib/public/Notification/INotification.php b/lib/public/Notification/INotification.php
index f71d0c53cc..29f2a0e794 100644
--- a/lib/public/Notification/INotification.php
+++ b/lib/public/Notification/INotification.php
@@ -1,5 +1,4 @@
 <?php
-declare (strict_types = 1);
 /**
  * @copyright Copyright (c) 2016, ownCloud, Inc.
  *
@@ -37,7 +36,7 @@ interface INotification {
 	 * @throws \InvalidArgumentException if the app id is invalid
 	 * @since 9.0.0
 	 */
-	public function setApp(string $app);
+	public function setApp($app);
 
 	/**
 	 * @return string
@@ -51,7 +50,7 @@ interface INotification {
 	 * @throws \InvalidArgumentException if the user id is invalid
 	 * @since 9.0.0
 	 */
-	public function setUser(string $user);
+	public function setUser($user);
 
 	/**
 	 * @return string