Translation tag displayed when using multiple referrer-policy values

[WKobes]

See: https://internet.nl/site/github.com/3159118/#control-panel-30

Multiple referrer-policy values is valid: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy#specify_a_fallback_policy

[WKobes]

https://www.w3.org/TR/referrer-policy/#parse-referrer-policy-from-header

[WKobes]

https://internet.nl/site/mastodon.nl/3159147/#control-panel-30

[bwbroersma]

Very interesting how this crashes with github.com, and when it does not:
https://dev-docker.internet.nl/site/kpsauqxtrrbf5prozsbxqjib.v1.b6a.nl/31737/#control-panel-30

$ curl https://github.com/ -sSfI --http1.1 | grep -i referrer
Referrer-Policy: origin-when-cross-origin, strict-origin-when-cross-origin

Isn't this plain invalid?

Related:

• Duplicate headers #1348

[WKobes]

@bwbroersma in your example there is no finding and therefore no translation tag. See for example:
https://internet.nl/site/kpcpadabe7vrb4uslye3aeaaaa.v1.b6a.nl/3159214/#control-panel-30

[bwbroersma]

Check, to conclude: the Referrer-Policy can be multiple value, which also means multiple headers are combined to one list of directives, where the last (valid) directive is picked, see the two samples below with 3 directives in 2 headers.

✅ Referrer-Policy ['origin-when-cross-origin', 'strict-origin-when-cross-origin', 'no-referrer'] (🪄 reverse / 🪄 input)
❌ Referrer-Policy ['no-referrer', 'origin-when-cross-origin', 'strict-origin-when-cross-origin'] (🪄 reverse / 🪄 input)