Facebook revised their cover image policy to be more consistent with the 20% text policy for news feed ad images.
They removed language restricting sales/purchase/price information, call-to-actions, or company websites from being on the cover image.
The policy now simply says:
“All covers are public. This means that anyone who visits your Page will be able to see your cover. Covers can’t be deceptive, misleading or infringe on anyone else’s copyright. You may not encourage people to upload your cover to their personal timelines. Covers may not include images with more than 20% text.”
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