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  1. Firefox Developer Tools
  2. The Firefox JavaScript Debugger
  3. How to
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How to

These articles describe how to use the debugger.

  • Access debugging in add-ons
  • Breaking on exceptions
  • Debug eval sources
  • Disable breakpoints
  • Highlight and inspect DOM nodes
  • Ignore a source
  • Open the debugger
  • Pretty-print a minified file
  • Search
  • Set a breakpoint
  • Set a conditional breakpoint
  • Set watch expressions
  • Step through code
  • Use a source map
  • Use watchpoints

Found a problem with this page?

  • Source on GitHub
  • Report a problem with this content on GitHub
  • Want to fix the problem yourself? See our Contribution guide.

Last modified: Sep 15, 2020, by MDN contributors

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Related Topics

  1. Page Inspector
  2. Web Console
  3. JavaScript Debugger
  4. Network Monitor
  5. Performance
  6. Application
  7. Responsive Design Mode
  8. Accessibility Inspector
  9. More Tools
    1. Memory
    2. Storage Inspector
    3. DOM Property Viewer
    4. Eyedropper
    5. Screenshot
    6. Style Editor
    7. Rulers
    8. Measure a portion of the page
    9. View Source
  10. Connecting the devtools
    1. about:debugging
    2. Connecting to Firefox for Android
    3. Connecting to iframes
    4. Connecting to other browsers
  11. Debugging the browser
    1. Browser Console
    2. Browser Toolbox
  12. Extending the devtools
  13. Settings
  14. Tips
  15. Release notes
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