I downloaded the main code only. Based on your recommendation, though, I'll break with policy and try out the PR. Thank you, Remy.
[Update] It worked. I see what you mean about the design time properties. It doesn't allow for explicitly configuring the IO handler for TLS 1.3, but if I make a connection to a server that implements 1.3, it works. That's good enough for now. Thank you, Remy and Mezen, for your hard work!