Does CodePen support JavaScript?

You can add JavaScript libraries to your Pen through the JavaScript settings menu . There are two ways to access the JavaScript settings menu. For quickest access, click the gear icon in the upper left of the JS editor panel. That opens the Pen Settings menu with the JavaScript tab automatically selected.

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How do I see errors in CodePen?

Red dots in the sidebar , indicating the errored file and all folders that contain it. That way if a file is a few levels deep, you’ll always be able to follow the dots down to find it. In the new logs, which show you the complete error output and includes a button to jump to that file.

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