I posted an item to a Facebook group. My post had a link to a Google Document which is a public document - anyone (who knows the link) can add to it.
The FTS Facebook widget shows the hyperlink as it was in the Facebook post, but it shows as plain text in the widget - not as a clickable link.
As well as that, the widget shows "Attachment Unavailable. This attachment may have been removed or the person who shared it may not have permission to share it with you."