The Facebook Video Cover feature is a new feature that Facebook is currently in the process of rolling out. It is available for some pages, but not others - and there appears to be no clear justification for who receives this feature and who does not.

The official message from Facebook on the subject: 

"The cover video feature is a new feature that is still being tested and is not yet available to all Pages. We don't have a timeline for when or if this feature will be available to all Pages, but we're glad you like the new feature!

We do make some changes to the platform based on the feedback we receive. If you'd like, you can submit your feedback or suggestions at any time with this form: 
https://www.facebook.com/help/contact/268228883256323/?ref=u2u"


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