Microsoft Edge, UnityWebRequest not working

I am having a problem with UnityWebRequests in the Edge Browser (Version 44.17763.1.0).
When calling the following code I get no connection to my server established when using edge browser.

Code (CSharp):

1. Uri uri = new Uri("http://localhost:1337/xyz");
2.  
3. using (UnityWebRequest www = new UnityWebRequest(uri, UnityWebRequest.kHttpVerbPOST))
4. {
5.     JSONRequest data = getRequestedData();
6.     var byteData= Encoding.ASCII.GetBytes( JsonUtility.ToJson(data) );
7.  
8.     www.timeout = 10;
9.     www.downloadHandler = new DownloadHandlerBuffer();
10.     www.uploadHandler = new UploadHandlerRaw(byteData);
11.     www.SetRequestHeader("Content-Type", "text/json");
12.  
13.     yield return www.SendWebRequest();
14.  
15.     if(www.isNetworkError || www.isHTTPError)
16.         throw new Exception("Error");  
17. }
18.  

There are no warnings or errors in the browser or debug console, just a TimeOut Exception is thrown.
In Firefox, the same code works fine.

Some additional Information:
Appears in both ASM.js and Webassembly,

I hope it can be helped because edge compatibility is important to us.
Greetings

 

I wrote a little example script to test the other HTTP verbs.

Code (CSharp):

1. using System;
2. using System.Collections;
3. using System.Text;
4. using TMPro;
5. using UnityEngine;
6. using UnityEngine.Networking;
7. using UnityEngine.UI;
8.  
9. public class ConnectionTest : MonoBehaviour
10. {
11.     Uri m_Uri = new Uri("http://localhost:1337/debug");
12.  
13.     public TMP_InputField m_Input;
14.  
15.     public Image m_Get;
16.     public Image m_Post;
17.     public Image m_Put;
18.     public Image m_Delete;
19.  
20.     private Color m_Color = new Color();
21.  
22.     // Start is called before the first frame update
23.     void Start()
24.     {
25.         m_Color = m_Get.color;
26.         m_Input.text = m_Uri.ToString();
27.         StartCoroutine(Load());      
28.     }
29.  
30.     // Update is called once per frame
31.     void Update()
32.     {      
33.     }
34.  
35.     IEnumerator Load()
36.     {
37.         yield return StartCoroutine(LoadRoutine(m_Uri, UnityWebRequest.kHttpVerbGET));
38.         yield return StartCoroutine(LoadRoutine(m_Uri, UnityWebRequest.kHttpVerbPOST));
39.         yield return StartCoroutine(LoadRoutine(m_Uri, UnityWebRequest.kHttpVerbPUT));
40.         yield return StartCoroutine(LoadRoutine(m_Uri, UnityWebRequest.kHttpVerbDELETE));
41.     }
42.  
43.     public void setUri(string uri)
44.     {
45.         if(!string.IsNullOrEmpty(uri) && !string.IsNullOrWhiteSpace(uri))
46.         {
47.             m_Get.color = m_Color;
48.             m_Post.color = m_Color;
49.             m_Put.color = m_Color;
50.             m_Delete.color = m_Color;
51.  
52.             m_Uri = new Uri(uri);
53.  
54.             StartCoroutine(Load());
55.         }
56.     }
57.  
58.     IEnumerator LoadRoutine(Uri uri, string requestType)
59.     {
60.         Debug.Log("Testing " + requestType + " to " + uri.ToString());
61.         using (UnityWebRequest www = new UnityWebRequest(uri, requestType))
62.         {
63.             //www.chunkedTransfer = true;
64.             //www.timeout = options.timeout;
65.             www.downloadHandler = new DownloadHandlerBuffer();
66.             if(requestType != UnityWebRequest.kHttpVerbGET)
67.             {
68.                 www.uploadHandler = new UploadHandlerRaw(Encoding.ASCII.GetBytes("test1234"));
69.                 www.SetRequestHeader("Content-type", "text/json");
70.             }
71.             yield return www.SendWebRequest();
72.  
73.             if (www.isHttpError)
74.                 Debug.LogError("HTTPError: " + www.error);
75.  
76.             if (www.isNetworkError)
77.                 Debug.LogError("NetworkError: " + www.error);
78.  
79.             bool hasError = www.isHttpError || www.isNetworkError;
80.             switch (requestType)
81.             {
82.                 case UnityWebRequest.kHttpVerbGET   : m_Get.color    = hasError ? Color.red : Color.green; break;
83.                 case UnityWebRequest.kHttpVerbPOST  : m_Post.color   = hasError ? Color.red : Color.green; break;
84.                 case UnityWebRequest.kHttpVerbPUT   : m_Put.color    = hasError ? Color.red : Color.green; break;
85.                 case UnityWebRequest.kHttpVerbDELETE: m_Delete.color = hasError ? Color.red : Color.green; break;
86.             }
87.  
88.             Debug.Log(www.downloadHandler.text);
89.         }
90.     }
91. }

Here is the copied edge console window.

Like I said, in Firefox everything is working fine.