I remember patching Netty https://github.com/netty/netty/pull/8653 just to get the master key in order to decrypt sessions.
Having the ability to decrypt TLS sessions like this is way simpler.
tl;dr; would love to see something like this for tshark / tcpdump
Perhaps OP's technique could be used to generate such a file.
EDIT: I see you have already investigated such methods after looking at your github link.
I remember patching Netty https://github.com/netty/netty/pull/8653 just to get the master key in order to decrypt sessions.
Having the ability to decrypt TLS sessions like this is way simpler.
tl;dr; would love to see something like this for tshark / tcpdump