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On Windows (versions before 11.0.0.0), you can fully debug your Javascript running in Pulsar by using the Edge Developer Tools.
New for Windows 11.0.0.0+ - Use built-in developer tools! With Pulsar version 11 on Windows, you should debug your code using the built-in Edge Developer tools, which will be enabled for any user/document combination enabled for local development server use. The older Edge Developer Tools preview application will no longer work with Pulsar. To enable the built-in Developer Tools, right-click anywhere in the webview and choose Inspect.
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Also, if you prefer log (printf)-style debugging, you have direct access to the Pulsar logs at the following location on disk: C:\Users\<YourUserName>\AppData\Local\Packages\E3D1A000.PulsarforSalesforce_ta6n8xy84gcpg\LocalState\Library\Application Support\log.txt
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