/// <summary>
        /// Loads a stylesheet resource via its URL.
        /// </summary>
        /// <param name="context">The context to use.</param>
        /// <param name="address">The address of the resource.</param>
        /// <param name="element">The hosting element.</param>
        /// <param name="cancel">The cancellation token.</param>
        /// <returns>The async task.</returns>
        public static async Task <IStyleSheet> OpenStyleSheetAsync(this IBrowsingContext context, Url address, IElement element, CancellationToken cancel)
        {
            var loader  = context.GetService <IResourceLoader>();
            var service = context.GetCssStyling();

            if (loader != null && service != null)
            {
                var request  = element.CreateRequestFor(address);
                var download = loader.FetchAsync(request);

                using (var response = await download.Task.ConfigureAwait(false))
                {
                    var options = new StyleOptions(element?.Owner ?? context.Active)
                    {
                        Element = element
                    };
                    return(await service.ParseStylesheetAsync(response, options, cancel).ConfigureAwait(false));
                }
            }

            return(null);
        }