Also disable back when we have no history stack.

This is useful for when we open a page directly in an inner link.

src/App.tsx

@@ -94,6 +94,7 @@ const AppBarWitHistory = withRouter(
 
     canGoBack() {
       return (
+        (this.props.history!.length > 1) &&
         (this.props.history!.location.pathname !== routeResolver.getRoute('pim')) &&
         (this.props.history!.location.pathname !== routeResolver.getRoute('home'))
       );