You can swap a layout with a layout from either a template or an existing app at any time.
To swap the layout:
1.While editing your app in Web Designer, select the tab of the layout you want to swap.
2.Click the three-dot menu beside the layout tab.
The layout tab menu appears.
3.In the layout tab menu, click Swap Layout.
The Select an App dialog appears.
4.Select a template or app whose layout you want to apply to the current app, and click Next.
5.Click File > Save.