Why sync context is not working for await?

This answer says

by default the await operator will capture the current "context" and use that to resume the async method.

I am trying this code in my console app:

static void Main(string[] args)
{
    Test().Wait();
}

private static async Task Test()
{
    var context = new SynchronizationContext();
    SynchronizationContext.SetSynchronizationContext(context);
    Console.WriteLine("Thread before: " + Thread.CurrentThread.ManagedThreadId);
    Console.WriteLine(await GetResultAsync());
    Console.WriteLine("Thread after: " + Thread.CurrentThread.ManagedThreadId);
}

private static async Task<string> GetResultAsync()
{
    return await Task.Factory.StartNew(() =>
    {
        Console.WriteLine("Thread inside: " + Thread.CurrentThread.ManagedThreadId);
        return "Hello stackoverflow!";
    });
}

... and get this out:

Thread before: 1
Thread inside: 3
Hello stackoverflow!
Thread after: 3

Why? And also how I should set sync context if I want to use the same thread after await?