Elsewhere, @hsivonen wrote:

While implementing redaction, I noticed that by spec, when redaction is not
in use, when the request promise resolves, both the request and the response
have the full address, but when redaction is in use, when the request
promise resolves, only the response has the full address and the redacted
address remains in the request. This seems like a footgun: Web developers
who test with a browser that doesn't redact might, at the time of the
request promise resolving, mistakenly pull the shipping address from the
request object instead of the response object and it would work in browsers
that don't redact and break in browsers that do redact.