method FlattenedEncrypt.prototype.setProtectedHeaderimport { FlattenedEncrypt } from "https://dotland.deno.dev/x/jose@v5.9.2/index.ts"; setProtectedHeader(protectedHeader: JWEHeaderParameters): thisSets the JWE Protected Header on the FlattenedEncrypt object. ParametersprotectedHeader: JWEHeaderParametersJWE Protected Header. Returnsthis