Debugging JavaScript With A Real Debugger You Did Not Know You Already Have

console.log can tell you a lot about your app, but it can’t truly debug your code. For that, you need a full-fledged JavaScript debugger. The new Firefox JavaScript debugger can help you write fast, bug-free code. Here’s how it works. In this example, we’ll crack open a very simple to-do app with Debugger. Here’s the app, based on basic open-source JavaScript frameworks. Open it up in the latest version of Firefox Developer Edition and then launch debugger.
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