Removed some unnecessary changes, turned out it was a simple cache issue.

This fixes #2699
This fixes #2635

Duplicati/Server/WebServer/AuthenticationHandler.cs

@@ -51,9 +51,6 @@ namespace Duplicati.Server.WebServer
         {
             string xsrftoken = request.Headers[XSRF_HEADER_NAME] ?? "";
 
-            if (!string.IsNullOrWhiteSpace(xsrftoken))
-                xsrftoken = Duplicati.Library.Utility.Uri.UrlDecode(xsrftoken);
-
             if (string.IsNullOrWhiteSpace(xsrftoken))
             {
                 var xsrfq = request.Form[XSRF_HEADER_NAME] ?? request.Form[Duplicati.Library.Utility.Uri.UrlEncode(XSRF_HEADER_NAME)];
@@ -77,8 +74,7 @@ namespace Duplicati.Server.WebServer
             var buf = new byte[32];
             var expires = DateTime.UtcNow.AddMinutes(XSRF_TIMEOUT_MINUTES);
             m_prng.GetBytes(buf);
-            // Don't use non-safe chars, as the current webserver has some "trouble" parsing it
-            var token = BitConverter.ToString(buf).Replace("-", string.Empty); //Convert.ToBase64String(buf);
+            var token = Convert.ToBase64String(buf);
 
             m_activexsrf.AddOrUpdate(token, key => expires, (key, existingExpires) =>
             {