Just FYI Boarding a flight (Delta/AF) that layovers in the EU but landing in a non-EU country the check-in agent said I should have the physical card or a photocopy, no digital. She then said never-mind as I'm only laying over. So I'm unsure on the layover rules but if you are going there they need to see the physical card OR photocopy which is laughable considering digital is the same. To twist it up even more, My friend flying United/Partner digital card was fine no questions asked with an EU layover.
I traveled just at the end of August where my digital copy was fine to use around Paris or a negative test.