thumbnailLink property
A short-lived link to the file's thumbnail, if available.
Typically lasts on the order of hours. Not intended for direct usage on
web applications due to [Cross-Origin Resource Sharing
(CORS)](https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS) policies,
consider using a proxy server. Only populated when the requesting app can
access the file's content. If the file isn't shared publicly, the URL
returned in Files.thumbnailLink
must be fetched using a credentialed
request.
Output only.
Implementation
core.String? thumbnailLink;