Deterministically derive key pair from secret, salt, and context?

To implement (message layer security)[https://github.com/mlswg/mls-protocol/blob/main/draft-ietf-mls-protocol.md] in the browser, a client needs to be able to derive a key pair from a secret, salt, and context, e.g. something like this:

window.crypto.subtle.deriveKey(
      {
        name: "HKDF",
        hash: {name: "SHA-512"},
        salt: salt,
        info: context
      },
      secret,
      {name: "ECDSA", namedCurve: "P-384"},
      true,
      ["sign", "verify"]);

Could this be added to the spec?

Review the Message Layer Security protocol draft linked in the issue alongside the Web Cryptography API specification. Determine whether deterministic key-pair derivation belongs in the API and what requirements the proposed operation would need; done means a documented specification decision or a concrete proposal accepted by maintainers.