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Duplicating the files of the default theme is easy, and even that can be done using two different ways.
From the back
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office
PrestaShop's back - office can help you create a new theme folder based on any other installed theme, all in a couple of clicks:
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All these module templates are included by default in the default theme's /modules
folder, because they are front-end features that are needed by that theme. You can safely disable/uninstall any other module in the back - office "Modules" page. This enables you to start on a somewhat clean slate.
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