diff --git a/frontend/src/network/uploading.ts b/frontend/src/network/uploading.ts
index 8d7ba8e..d17efa9 100644
--- a/frontend/src/network/uploading.ts
+++ b/frontend/src/network/uploading.ts
@@ -187,4 +187,11 @@ class UploadingManager extends Listenable {
   }
 }
 
-export const uploadingManager = new UploadingManager();
\ No newline at end of file
+export const uploadingManager = new UploadingManager();
+
+window.addEventListener("beforeunload", () => {
+  if (uploadingManager.hasTasks()) {
+    return "Uploading files, are you sure you want to leave?";
+  }
+  return undefined;
+})
\ No newline at end of file