Github markdown - online TLS 1.2

[rev]

github has deprecated TLS 1.0 and 1.1 in their markdown parser. please update markdownpad to negotiate with TLS 1.2.

see https://github.com/AuthorizeNet/sdk-dotnet/issues/199

markdownpad preview renders this in browser:

An error occurred while processing GitHub Flavored Markdown.
The request was aborted: Could not create SSL/TLS secure channel.
If the problem persists, please report the bug.

[kingkeith]

see this thread for how to work around this:

GFM online mode SSL/TLS secure channel aborts

my understanding is that MDP2 is built with .NET Framework v4.0, which doesn't support TLS 1.2 or use it by default. but if you have .NET Framework 4.5 installed, you can update some registry settings and restart MDP2 and GitHub Flavoured Markdown Online starts working again