Recording a Packet Trace

I want to track down which part of an app contacts a given domain listed in its App Privacy Report.

Following the instructions given here I am able to capture a packet trace, but traffic to the domain in question is encrypted using QUIC.

Is there a way to insert e.g. mitmproxy into the capture process in order to get hold of the SSLKEYLOGFILE so that I can decrypt the traffic?

Recording a Packet Trace
 
 
Q