Prismic Preview is not working in my .net website

I have an MVC .Net application and am struggling to put the prismic preview working.
Basically when I put the following script in the page, the page reloads and overrides the cookie and then I am getting the normal data instead of the changes. That reload seems to happen due to this script that prismic is advising to put on the page:

<script async defer src=""></script>

Here it is my Preview Action:

const string isPreviewParam = "isPreview=1";

		public async Task<ActionResult> Preview(string token)
            var ctx = await getContext(false);
			string url = await ctx.Api.PreviewSession (token, ctx.LinkResolver, "/") + "&" + isPreviewParam;
			var cookie = new HttpCookie (prismic.Api.PREVIEW_COOKIE, token);
			cookie.Expires = DateTime.Now.AddMinutes (30);
			return Redirect(url);

Action to show the page:

public async Task<ActionResult> Detail(string id, string slug)
			var ctx = await getContext(isPreview(HttpContext.Request.Url.ToString()));
            var response = await ctx.Api.Form("everything")
				.Query("", id))
				.Ref (ctx.MaybeRef)
				.Submit (); 

			var document = response.Results.FirstOrDefault ();
			if (document != null && document.Slug == slug) {
				ViewBag.Title = "Document detail " + slug;
				return View (new PrismicDocument (ctx, document));
			else if (document != null && document.Slugs.Contains(slug)) {
				return RedirectToActionPermanent ("Detail", new { id, document.Slug });
			} else {
				ViewBag.Title = "Document not found";
				this.Response.StatusCode = 404;
				return View ("PageNotFound", new PrismicViewModel(ctx));

And the get context method:

private async Task<PrismicContext> getContext(bool isPreview)
			var endpoint = WebConfigurationManager.AppSettings.Get("prismic.api.url");
			var api = await new PrismicApiHome(endpoint).Get();

			HttpCookie previewCookie = isPreview ? HttpContext.Request.Cookies.Get(prismic.Api.PREVIEW_COOKIE) : null;

			string maybeRef = (previewCookie != null && previewCookie.Value != "")
				? previewCookie.Value
				: api.Master.Reference;
			return new PrismicContext(endpoint, api, maybeRef, PrismicLinkResolver.Get(api, maybeRef, ControllerContext.RequestContext));

This how the cookie looks like when I remove the JavaScript mentioned above (without reloading)

This how the cookie looks like with the JavaScript, it reloads and smashed the previous cookie value and I see the live prismic value instead of the preview.


Any idea why? What am I doing wrong?

Hi Vitor,
Thanks for reaching out, some other users has reported a similar issue and we are investigating it and we will keep you informed about any updates: