I'd like to get WebKit's position on: (1) Having an explicit upper limit for Cookie Expires/Max-Age attributes (2) Having an explicit upper limit for Cookie Expires/Max-Age attributes that's less than or equal to 400 days https://httpwg.org/http-extensions/draft-ietf-httpbis-rfc6265bis.html#name-t... https://github.com/httpwg/http-extensions/pull/1732 https://github.com/mozilla/standards-positions/issues/592 https://bugs.chromium.org/p/chromium/issues/detail?id=1264458 The draft of rfc6265bis now contains an upper limit for Cookie Expires/Max-Age attributes. As written: `The user agent MUST limit the maximum value of the [Max-Age/Expiration] attribute. The limit MUST NOT be greater than 400 days (34560000 seconds) in duration. The RECOMMENDED limit is 400 days in duration, but the user agent MAY adjust the limit to be less. [Max-Age/Expiration] attributes that are greater than the limit MUST be reduced to the limit.` 400 days was chosen as a round number close to 13 months in duration. 13 months was chosen to ensure that sites one visits roughly once a year (e.g., picking health insurance benefits) will continue to work. Safari is already partially compliant (has an upper age limit of 7 days when cookies are set client side), while Firefox and Chrome both support cookies with expiration dates orders of magnitude longer than a millenia in the future. According to measurements in Chrome of all cookies set about 20% have an Expires/Max-Age further than 400 days in the future. Of that 20%: half target 2 years, a quarter target 10 years or more, and the remainder are spread over the rest of the range. ~ Ari Chivukula (Their/There/They're)