Before you edit it you want to export a copy to the desktop then import it and give it a different name. Then you can delete the bottom half from popup 1 and delete the top half from popup 2. The export/import button is in the upper left corner just to the right of the Delete button as shown in the attached image.
p.s. You may want to keep that desktop copy of the original backed up on the desktop or elsewhere in case you ever want to import/use the original popup again in the future.
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