TLS dissectors missing in "decode as" feature (ex: TPKT)

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Hi. I've been working with Wireshark quite a bit, and when I compiled wireshark from source on ubuntu 18, I had a TLS subdissector for "TPKT". However, when my colleague compiled from source with the same OS, he did not have it, it was simply missing. We were at the same commit.

Now, I downloaded the latest version of wireshark for windows ( https://puu.sh/DBL3p/6662fa3bc2.png ) and I still don't see the TPKT dissector in the TLS "decode as" feature: https://puu.sh/DBL4q/02b1eb12e0.png

What might cause this? I'm trying to decode RDP traffic, so I really need the TPKT dissector.

I've tried to manually edit the decode_as_entries file, but it did not work.

Thanks for your time, --Émilio