fix cowebsite

front/src/WebRtc/CoWebsiteManager.ts

@@ -148,6 +148,7 @@ class CoWebsiteManager {
             setTimeout(() => resolve(), 2000);
         });
         this.currentOperationPromise = this.currentOperationPromise.then(() =>Promise.race([onloadPromise, onTimeoutPromise])).then(() => {
+            this.cowebsiteMainDom.appendChild(iframe);
             this.open();
             setTimeout(() => {
                 this.fire();