diff --git a/lib/private/Preview/Movie.php b/lib/private/Preview/Movie.php
index b7b7c98e50f04..57cf9ddeaf4b8 100644
--- a/lib/private/Preview/Movie.php
+++ b/lib/private/Preview/Movie.php
@@ -52,9 +52,9 @@ public function getThumbnail(File $file, int $maxX, int $maxY): ?IImage {
 		$absPath = $this->getLocalFile($file, 5242880); // only use the first 5MB
 
 		$result = $this->generateThumbNail($maxX, $maxY, $absPath, 5);
-		if ($result === false) {
+		if ($result === null) {
 			$result = $this->generateThumbNail($maxX, $maxY, $absPath, 1);
-			if ($result === false) {
+			if ($result === null) {
 				$result = $this->generateThumbNail($maxX, $maxY, $absPath, 0);
 			}
 		}