diff --git a/chrome/content/zotero/xpcom/server_connector.js b/chrome/content/zotero/xpcom/server_connector.js
index ee4a83a4b..ede4d09df 100644
--- a/chrome/content/zotero/xpcom/server_connector.js
+++ b/chrome/content/zotero/xpcom/server_connector.js
@@ -355,8 +355,14 @@ Zotero.Server.Connector.SaveItem.prototype = {
 			}
 		}
 		
-		var cookieSandbox = data["uri"] ? new Zotero.CookieSandbox(null, data["uri"],
-			data["detailedCookies"] ? "" : data["cookie"] || "", options.userAgent) : null;
+		var cookieSandbox = data.uri
+			? new Zotero.CookieSandbox(
+				null,
+				data.uri,
+				data.detailedCookies ? "" : data.cookie || "",
+				options.headers["User-Agent"]
+			)
+			: null;
 		if(cookieSandbox && data.detailedCookies) {
 			cookieSandbox.addCookiesFromHeader(data.detailedCookies);
 		}
@@ -466,7 +472,9 @@ Zotero.Server.Connector.SaveSnapshot.prototype = {
 			filesEditable = true;
 		}
 		
-		var cookieSandbox = new Zotero.CookieSandbox(null, data["url"], data["cookie"], options.userAgent);
+		var cookieSandbox = new Zotero.CookieSandbox(
+			null, data.url, data.cookie, options.headers["User-Agent"]
+		);
 		
 		if (data.pdf && filesEditable) {
 			delete Zotero.Server.Connector.Data[data.url];