Collab Mode is a PRO feature of CodePen that allows more than one person to edit a Pen at the same time . If you’ve ever used collaborative editing in Google Docs, it’s a lot like that!
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A project editor supports multiple HTML, CSS, and JavaScript files. With the free account, you can only have one project and 10 files . If you are interested in creating more projects, you will need to upgrade to the Pro account.
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