fix converting mp4

app/api/routes/node_storage.py

@@ -211,7 +211,7 @@ async def s_api_v1_storage_get(request, file_hash=None):
 
         elif content_type == 'video':
             # Build a temp path for the video
-            tempfile_path += "_mp4" + (f"_{seconds_limit}" if seconds_limit else "")
+            tempfile_path += "_mp4" + (f"_{seconds_limit}" if seconds_limit else "") + ".mp4"
             if not os.path.exists(tempfile_path):
                 try:
                     # Use ffmpeg to cut or convert to mp4