Updater error : Couldn't query GITHUB API

[jcaillon]

Description of the Issue

Since February 22 the 3P automatic updater is not working and displays a message saying it failed to query the github API.

Why is this happening?

The 3P updater is using the github API to check for new releases and download the .zip file. Last Thursday, GitHub turned off some weak crypto standards; including TLSv1.1. You can read about this here.

How is it related you ask? I've build 3P around the .NET framework v4.0 which only supports TLSv1.1. This is the default security protocol and also the latest protocol supported by this version.

What does it mean for 3P?

I will have to upgrade the project to .NET 4.6.2 https://www.microsoft.com/en-us/download/details.aspx?id=53344.
That also means that 3P will not be able to run on windows versions inferior to windows 7. For the few users still stuck in windows vista (or xp??) there is still the option to use the latest compatible version which is 1.8.0.
Fortunately, 3P is present in the plugin manager so there is still a way to update the plugin automatically for most users. However, i'm afraid this will not cover a 100% of the users, some will have to update manually :/
I could have targeted a lower version of .net (4.5 would have been enough), but I want to be able to use C#6.0 features in future developments of 3P (selfish me!).

Technical details

In 4.6 and above TLSv1.2 is the default protocol.
In 4.5 the protocol is supported but we have to force the default security procotol with ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12.
In 4.0 (our version) we can force TLSv1.2 if the user has 4.5 installed on his machine : ServicePointManager.SecurityProtocol = (SecurityProtocolType)3072;