A cookies helper class to easily read and set cookies on HttpRequest (Asp.Net Core)

cookieshelper.cs

public class CookiesHelper
{

	// Inspired from:
	// https://github.com/aspnet/Mvc/blob/538cd9c19121f8d3171cbfddd5d842cbb756df3e/test/Microsoft.AspNet.Mvc.FunctionalTests/TempDataTest.cs#L201-L202

	public static IDictionary<string, string> ExtractCookiesFromResponse(HttpResponseMessage response)
	{
		IDictionary<string, string> result = new Dictionary<string, string>();
		IEnumerable<string> values;
		if (response.Headers.TryGetValues("Set-Cookie", out values))
		{
			SetCookieHeaderValue.ParseList(values.ToList()).ToList().ForEach(cookie =>
			{
				result.Add(cookie.Name, cookie.Value);
			});
		}
		return result;
	}

	public static HttpRequestMessage PutCookiesOnRequest(HttpRequestMessage request, IDictionary<string, string> cookies)
	{
		cookies.Keys.ToList().ForEach(key =>
		{
			request.Headers.Add("Cookie", new CookieHeaderValue(key, cookies[key]).ToString());
		});

		return request;
	}

	public static HttpRequestMessage CopyCookiesFromResponse(HttpRequestMessage request, HttpResponseMessage response)
	{
	    return PutCookiesOnRequest(request, ExtractCookiesFromResponse(response));
	}
}

According to RFC 6265, Section 5.4:

When the user agent generates an HTTP request, the user agent MUST NOT attach more than one Cookie header field.

As such, I believe this implementation isn't quite right since it will result in multiple Cookie headers being set.