How to use the debugger in Chrome DevTools? How to set a breakpoint on a third-party website without access to source code?

In Chrome DevTools, the debugger allows you to set breakpoints to pause JavaScript execution and examine the program's state.

To set a breakpoint on a third-party website without access to the source code:

1. Open DevTools (F12 or Ctrl+Shift+I).
2. Go to the Sources tab.
3. Find the desired script in the file list. If the code is minified, you can click the Pretty print ({}) button to format it.
4. Set a breakpoint by clicking on the line number.

If the source code is unavailable or the script is loaded dynamically, you can:

• Use Event Listener Breakpoints (in the right Sources panel) — set breakpoints on specific events (e.g., clicks, loads, etc.).
• Use XHR/fetch Breakpoints to pause on network requests.
• Manually insert debugger; via the console if you can execute code on the page.

This way, even without direct access to the source code, you can investigate the website's behavior and debug it.