Proton Pass credit card entries should natively support and autofill a postal code/zip code field in the card schema (along with name, card number, expiration date, etc.).  

Reason: many sites require a postal code entry to be included along with #, name, code, etc. to help in security/billing verification. 

Benefit: more seamless credit card autofill for users without having to enter the postal code manually or hope for a second step identity autofill.