The API works, but Stream web UI doesn't

The API works, but Stream web UI doesn't work for videos requiring Signed URLs: You can create a new AI-generated English caption, you can wait for it to be in the "Ready" state and then "Download" from the "..." menu. But the downloaded en.vtt file just contains text "401 unauthorized". Captions aside, the Stream UI is challenging to use for videos that require signed URLs. There are no previews or poster images visible, so navigation is limited by either filename or record-keeping in an external system.