Fixed custom widgets editor configuration view (#2686)

Co-authored-by: Roman I. Kolesnikov false <rokolesnikov@microsoft.com>

Author: rkolesnikovDX

src/components/custom-widget/ko/customWidgetEditorViewModel.ts

@@ -24,7 +24,7 @@ export class CustomWidgetEditorViewModel implements WidgetEditor<CustomWidgetMod
     public readonly src: ko.Observable<string>;
     public readonly instanceId: ko.Observable<string>;
     public readonly iframeAllows: string = iframeAllows;
-    public readonly iframeSandboxAllows: string = iframeSandboxAllows;
+    public readonly iframeSandboxAllows: string = CustomWidgetEditorViewModel.buildSandboxParams();
 
     constructor(
         private readonly viewManager: ViewManager,
@@ -69,6 +69,10 @@ export class CustomWidgetEditorViewModel implements WidgetEditor<CustomWidgetMod
         this.src(widgetSource.src);
     }
 
+    private static buildSandboxParams() {
+        return iframeSandboxAllows + " allow-same-origin";
+    }
+
     private updateResponsiveObservables(): void {
         if (!this.model.styles) {
             return;