network can now return "mastercard"

What changed

Producer-side tools call this additive. It breaks exhaustive switches, strict parsers and generated client enums.

Affects network on issuing.settlement reachable from 4 operations.

New value: mastercard.

can now return "mastercard"

Who is affected

Code that reads Stripe's issuing.settlement objects, used by 4 Stripe operations.

Before and after

Code that breaks

switch (response.network) {
  // existing branches …
  // no branch for "mastercard"
  default:
    throw new Error("unexpected network");
}

Based on Stripe’s published API specification. How severity is decided.