If you’ve upgraded to .NET Framework v4.8 you can use HttpCookieFilter in .NET Framework, e.g:
public override void HttpCookieFilter(HttpCookie cookie)
{
cookie.SameSite = SameSiteMode.None;
}
Why can’t you set it here?
Since this is .NET Framework you can access the Request Context from the HttpContext.Current singleton, e.g:
HttpRequest aspReq = HttpContext.Current.Request;
You can also create a new IRequest from HttpContext.Current with:
IRequest req = HostContext.TryGetCurrentRequest();