URL Preview (Unfurl) for authenticated links is not useful to show
Many of the links that are posted in our Teams are for things that exist behind a login page. When this happens the preview is of a login page which adds zero value. I do not manage our Teams instance so I can't turn off the feature entirely but it seems that a sane default would be using heuristics (or maybe something simpler) to detect a redirect to a login page and not show the preview.
