open link in the same window

Viewer/src/templating/plugins/printButton.ts

@@ -35,7 +35,7 @@ export class PrintButtonPlugin extends AbstractViewerNavbarButton {
     onEvent(event: EventCallback): void {
         if (this._currentModelUrl) {
             let printUrl = this._currentModelUrl.replace(/https?:\/\//, "com.microsoft.builder3d://");
-            window.open(printUrl);
+            window.open(printUrl, "_self");
         }
     }