The comments got me wondering about what a cookie can actually contain so I looked it up. A cookie can "include any US-ASCII character excluding a control chara

The comments got me wondering about what a cookie can actually contain so I looked it up. A cookie can "include any US-ASCII character excluding a control character, Whitespace, double quotes, comma, semicolon, and backslash." Browsers typically restrict length to 4096 bytes. So "small text file" seems like a reasonable description. (The interesting distinction is text vs binary.) https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Se...