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After doing a lot of research, finally I developed a working solution: https://stackoverflow.com/a/72638944/3701102

But what is the name of the process we need to do in order to validate the JWT? Because the libraries have a lot of functionality and there is no documentation from Apple to know where to start. Some libraries requires a "public key", another libraries requires a "private key", some methods requires a "passphrase", where do I get those things from the Apple?