Following the documentation for (pre-)master key decryption I've placed my key in form RSA Session-ID:xxxx Master-Key:yyyy to a file, but for some reason Wireshark won't decrypt the dump. I am using TLS1.2 with TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 (recognized by Wireshark). The debug log with decryption is here:
https://gist.github.com/rvansa/a75479dabac23b4435eacef91c185fd4
I am not sure which of the error-ey messages are red herrings and which actually apply.
