Hello,
I was working through the code and saw that in the certs.py file, the function dummy_cert() takes the following parameters: privkey, cacert, commonname, sans.
The comment in this function says: privkey: CA private key; thus meaning it is the private key from the mitmproxy-ca. If this is true, then the private key used in that function and the private key in the mitmproxy-ca.pem file should be the same or?
Why I ask is, i compared those two, and those are not equal, maybe I am wrong, help would be appreciated 
Best regards,
PM