Airtable creates thumbnail images for attachments that are images, pdf files, and other file formats that lend themselves to thumbnail images. These attachments are mostly for internal use by Airtable when displaying the attachments at different row heights.
You can access the urls for these thumbnails through scripting or the Web API. You have no control over the size of these thumbnails, and the urls expire.
Occasionally when a file is uploaded, the thumbnail fails to generate. You cannot manually request thumbnail generation, so if you need a thumbnail, re-upload the file.
Thumbnails
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