Step 1: create a self-signed root certificateFirst, let’s create a self-signed root certificate:The parameter -days 390 sets the number of days, this certificate is valid. Starting on September 1st (2020), SSL/TLS certificates cannot be issued for longer than 13 months (397 days), see https://stackoverflow.com/a/65239775.If this time is too long, you will receive an NET::ERR_CERT_VALIDITY_TOO_LONG error. […]