The actual official style guideline says about Cover Art:
The cover art for a release must always exactly match the actual art for that specific release . Artwork for a release should not be added to another release: for example, digipaks are not square, and a square digital front cover should not be uploaded to a digipak release.
Does this mean that is better to have no cover at all then a square front cover for all the digital media releases here on MB?
Do we speak about the format “Digital Media” or only the packaging “Digipak”?
Or does the term “should not be uploaded” means: Only do that for informational reasons if no cover isn’t yet available at MB/CAA - such an upload is not explicitely forbidden?