> JWT needs it for example (and I'd assume many signature models)
You almost never need canonical representations for signing things. I would even say that if you need a canonical representation to sign your things, then that is a design smell of your cryptographic protocol.
You don't _need_ canonical representations for signing, but then you can't let go of the representation used for computing the signature. What is the argument against a requirement to only sign canonical data?
You almost never need canonical representations for signing things. I would even say that if you need a canonical representation to sign your things, then that is a design smell of your cryptographic protocol.