After December 18, 2017, link preview customization for Facebook Page posts will no longer be supported for links that are not your own. See details below This follows Facebook’s deprecation of customization for group and profile posts that occurred in July, to reduce misrepresentation of link content. These changes apply to all Facebook’s API integration partners, including Hootsuite.
Posting links from other people’s websites
It will no longer be possible to customize the image, title or description of a link preview in a Page post. When sharing links to other people's websites, Facebook will pull link previews from the website's metadata. If this metadata is not available, a complete link preview with an image may not be generated.
See Facebook’s documentation to ensure that your own website is set up to generate optimal link previews.
Page posts scheduled to publish after December 18 will do so 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.
Posting links from your own domains
Facebook has enabled a tool in the Facebook Business Manager to let businesses continue customizing Page post previews for links to their own domains. It’s called Domain Verification. Follow these steps to verify your domain(s) and associate your Facebook Page(s) to these domains, so that you can continue customizing your Page post link previews.
Hootsuite's new Composer will also support link preview customization for verified domains.