diff --git a/build/psalm-baseline.xml b/build/psalm-baseline.xml
index e9f15ae8171..9b08cc9c28c 100644
--- a/build/psalm-baseline.xml
+++ b/build/psalm-baseline.xml
@@ -3705,12 +3705,6 @@
       <code><![CDATA[$this->cache instanceof Cache]]></code>
     </RedundantCondition>
   </file>
-  <file src="lib/private/Files/Cache/Wrapper/CacheWrapper.php">
-    <LessSpecificImplementedReturnType>
-      <code><![CDATA[array]]></code>
-      <code><![CDATA[array]]></code>
-    </LessSpecificImplementedReturnType>
-  </file>
   <file src="lib/private/Files/Config/MountProviderCollection.php">
     <InvalidOperand>
       <code><![CDATA[$user]]></code>
diff --git a/lib/private/Files/Cache/Wrapper/CacheWrapper.php b/lib/private/Files/Cache/Wrapper/CacheWrapper.php
index bf23f1cc30a..8d48fd2ddaa 100644
--- a/lib/private/Files/Cache/Wrapper/CacheWrapper.php
+++ b/lib/private/Files/Cache/Wrapper/CacheWrapper.php
@@ -100,14 +100,14 @@ class CacheWrapper extends Cache {
 	}
 
 	/**
-	 * get the metadata of all files stored in $folder
+	 * Get the metadata of all files stored in given folder
 	 *
 	 * @param int $fileId the file id of the folder
-	 * @return array
+	 * @return ICacheEntry[]
 	 */
 	public function getFolderContentsById($fileId) {
 		$results = $this->getCache()->getFolderContentsById($fileId);
-		return array_map([$this, 'formatCacheEntry'], $results);
+		return array_filter(array_map($this->formatCacheEntry(...), $results));
 	}
 
 	/**