REST API / websocket : subscribe to sitemap does not work

I’m trying to subscribe to REST API bt can’t get it working fro sitemap.
It works fine for items and groups, but absolutely nothing happen whit sitemap.
I try different URL, which works fine in a web browser, but nothing happen when items are updated.
I use client side javscript. Here after are my simple test files :

OH is version 1.8 build 1106 (which works fine for about 2,5 years and differents upgrades ).

I certainly missing something…
Any help really appreciated.


sitemap Dashboard label=“Test” {
Frame label=“Frame 1” {
Text item=EnergyUsagePercent label=“Electricity [%d%%]”


function subscribeWebsocket_DEBUG(URL) {
var wsSocket = new WebSocket(URL);

wsSocket.onopen = function()
	console.log("OPEN: wsSocket.onopen: "+URL);

wsSocket.onmessage = function(evt)
	console.log("MESSAGE: wsSocket.onmessage: \n" + "\n\n");

wsSocket.onclose = function(evt)
	console.log("CLOSED: wsSocket.onclose: "+URL);

wsSocket.onerror = function(error)
	console.log("ERROR: wsSocket.onerror: "+URL);


function subscribeItems() {
// Works fine
subscribeWebsocket_DEBUG(“ws://” + “?Accept=application/json”);

// Doesn't work
subscribeWebsocket_DEBUG("ws://" + "?Accept=application/json");
// Message in openhab.log: 
//[WARN ] [.w.protocol.SimpleHttpProtocol:152  ] - Status code higher or equal than 400. Unable to deliver the websocket messages to installed component. Status 404 Message Not Found

subscribeWebsocket_DEBUG("ws://" + "?Accept=application/json");
//[WARN ] [o.u.i.items.ItemUIRegistryImpl:471  ] - Cannot find page for id 'Dashboard'.


log message, when it works
MESSAGE: wsSocket.onmessage: