Duplazy is a free Chrome extension developed by davidsweetman. It falls under the category of Browsers and specifically the subcategory of Add-ons & Tools. This extension is designed to automatically duplicate commonly used characters such as brackets and quotations, making typing faster and providing a familiar experience to developer environments.

With Duplazy enabled, users can specify which characters they want the extension to automatically add the corresponding closing character for. Similar to how most IDEs handle this functionality, users can simply use the options page to select the supported characters they want to opt in. Duplazy will then take care of the rest while typing, adding the character and placing the typing cursor in between the duplicated characters.

Currently, Duplazy supports character pairings such as ( ), { }, [ ], and " ".