I originally asked this question on another forum, but was redirected here, maybe someone here can help me. Here is the original question, so that no need for me to retype it:
https://security.stackexchange.com/questions/210980/how-to-decrypt-diffie-hellman-encryption-in-webrtc/210995#210995
Please take a look, the currently one and only answer from 'blabla_trace' suggested I try my luck here as well.
