diff --git a/lib/base.php b/lib/base.php
index 05da2814d4..c5eabe1910 100644
--- a/lib/base.php
+++ b/lib/base.php
@@ -373,6 +373,7 @@ class OC {
 
 		// get third party apps
 		$ocVersion = \OCP\Util::getVersion();
+		$ocVersion = implode('.', $ocVersion);
 		$incompatibleApps = $appManager->getIncompatibleApps($ocVersion);
 		$incompatibleShippedApps = [];
 		foreach ($incompatibleApps as $appInfo) {
diff --git a/lib/private/App/AppManager.php b/lib/private/App/AppManager.php
index 690dcfe563..4bf15c23fa 100644
--- a/lib/private/App/AppManager.php
+++ b/lib/private/App/AppManager.php
@@ -397,7 +397,7 @@ class AppManager implements IAppManager {
 	 *
 	 * @internal
 	 */
-	public function getIncompatibleApps($version) {
+	public function getIncompatibleApps(string $version): array {
 		$apps = $this->getInstalledApps();
 		$incompatibleApps = array();
 		foreach ($apps as $appId) {