unregister a display if window closes

app/ui_screen.js

@@ -220,7 +220,9 @@ const UI = {
     },
 
     disconnect() {
-
+        if (UI.rfb) {
+            UI.rfb.disconnect();
+        }
     },
 
     connectFinished(e) {

core/display.js

@@ -418,9 +418,10 @@ export default class Display {
     }
 
     removeScreen(screenID) {
-        if (this.isPrimaryDisplay) {
+        if (this._isPrimaryDisplay) {
             for (let i=1; i<this._screens.length; i++) {
                 if (this._screens[i].screenID == screenID) {
+                    this._screens[i].channel.close();
                     this._screens.splice(i, 1);
                     return true;
                 }

core/rfb.js

@@ -770,11 +770,14 @@ export default class RFB extends EventTargetMixin {
     }
 
     disconnect() {
-        if (this._rfbConnectionState !== 'proxied') {
+        if (this._isPrimaryDisplay) {
             this._updateConnectionState('disconnecting');
             this._sock.off('error');
             this._sock.off('message');
             this._sock.off('open');
+        } else {
+            this._updateConnectionState('disconnecting');
+            this._unregisterSecondaryDisplay();
         }
     }
 
@@ -1676,6 +1679,17 @@ export default class RFB extends EventTargetMixin {
         
     }
 
+    _unregisterSecondaryDisplay() {
+        if (!this._isPrimaryDisplay){
+            let message = {
+                eventType: 'unregister',
+                screenID: this._display.screenId
+            }
+            this._controlChannel.postMessage(message);
+        }
+        
+    }
+
     _registerSecondaryDisplay() {
         if (!this._isPrimaryDisplay) {
             //let screen = this._screenSize().screens[0];