WhatsApp Phone Archiver processes media thumbnails and files downloaded.

If the media file is not downloaded with the message:

• The app continues to try downloading the file from the WhatsApp servers to the phone.
• The app checks the messages every 24 hours to check if the media, files, or attachments are downloaded to the phone.
• If the file is not downloaded, event after 24 hours, the media thumbnail is captured as an attachment along with the available information.

The message in the secondary storage repository indicates that the attachment is a thumbnail.