diff --git a/apps/dav/lib/Connector/Sabre/CommentPropertiesPlugin.php b/apps/dav/lib/Connector/Sabre/CommentPropertiesPlugin.php
index d5eb7062dd..add69367fc 100644
--- a/apps/dav/lib/Connector/Sabre/CommentPropertiesPlugin.php
+++ b/apps/dav/lib/Connector/Sabre/CommentPropertiesPlugin.php
@@ -47,8 +47,6 @@ class CommentPropertiesPlugin extends ServerPlugin {
 
 	private $cachedUnreadCount = [];
 
-	private $cachedFolders = [];
-
 	public function __construct(ICommentsManager $commentsManager, IUserSession $userSession) {
 		$this->commentsManager = $commentsManager;
 		$this->userSession = $userSession;
@@ -70,6 +68,31 @@ class CommentPropertiesPlugin extends ServerPlugin {
 		$this->server->on('propFind', [$this, 'handleGetProperties']);
 	}
 
+	private function cacheDirectory(Directory $directory) {
+		$children = $directory->getChildren();
+
+		$ids = [];
+		foreach ($children as $child) {
+			if (!($child instanceof File || $child instanceof Directory)) {
+				continue;
+			}
+
+			$id = $child->getId();
+			if ($id === null) {
+				continue;
+			}
+
+			$ids[] = (string)$id;
+		}
+
+		$ids[] = (string) $directory->getId();
+		$unread = $this->commentsManager->getNumberOfUnreadCommentsForObjects('files', $ids, $this->userSession->getUser());
+
+		foreach ($unread as $id => $count) {
+			$this->cachedUnreadCount[(int)$id] = $count;
+		}
+	}
+
 	/**
 	 * Adds tags and favorites properties to the response,
 	 * if requested.
@@ -91,11 +114,7 @@ class CommentPropertiesPlugin extends ServerPlugin {
 			&& $propFind->getDepth() !== 0
 			&& !is_null($propFind->getStatus(self::PROPERTY_NAME_UNREAD))
 		) {
-			$unreadCounts = $this->commentsManager->getNumberOfUnreadCommentsForFolder($node->getId(), $this->userSession->getUser());
-			$this->cachedFolders[] = $node->getPath();
-			foreach ($unreadCounts as $id => $count) {
-				$this->cachedUnreadCount[$id] = $count;
-			}
+			$this->cacheDirectory($node);
 		}
 
 		$propFind->handle(self::PROPERTY_NAME_COUNT, function () use ($node) {
@@ -109,18 +128,8 @@ class CommentPropertiesPlugin extends ServerPlugin {
 		$propFind->handle(self::PROPERTY_NAME_UNREAD, function () use ($node) {
 			if (isset($this->cachedUnreadCount[$node->getId()])) {
 				return $this->cachedUnreadCount[$node->getId()];
-			} else {
-				list($parentPath,) = \Sabre\Uri\split($node->getPath());
-				if ($parentPath === '') {
-					$parentPath = '/';
-				}
-				// if we already cached the folder this file is in we know there are no comments for this file
-				if (array_search($parentPath, $this->cachedFolders) === false) {
-					return 0;
-				} else {
-					return $this->getUnreadCount($node);
-				}
 			}
+			return $this->getUnreadCount($node);
 		});
 	}