When I ran my code, there was no definition. I don't know what happened.

[zhangyu1009e]

github.com/CUCyber/ja3transport

../../../pkg/mod/github.com/!c!u!cyber/ja3transport@v0.0.0-20201031204932-8a22ac8ab5d7/transport.go:57:13: undefined: tls.FakeCertCompressionAlgsExtension

Compilation finished with exit code 2

[reneManqueros]

this is an issue on the refraction utls repo, i fixed it by pinning a diff version on my go.mod:
replace github.com/refraction-networking/utls v1.3.2 => github.com/refraction-networking/utls v0.0.0-20200820030103-33a29038e742