As of July 17 at 11:59pm PST, Facebook will deprecate the ability to customize link previews for Facebook group and profile posts, in an effort to reduce misrepresentation of link content. These changes will apply to all of Facebook’s API integration partners, including Hootsuite.
It will no longer be possible to customize the image, title or description of a link preview in Facebook profile or group posts. Pages will not be affected by this change until a later date.
Facebook pulls link previews from website metadata. If you share a link to a website that is not your own, be aware that it may not have this metadata available. So a complete link preview with an image may not be generated in some cases.
Note that Facebook profile or group messages scheduled to post after July 17 will publish without any link customizations. The links will instead display their default metadata, if available.
See View, edit, or delete scheduled content to edit your scheduled messages.
Refer to Facebook’s documentation on sharing web-hosted content to ensure that links from your own sites are shared with optimal link preview data.