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.babel [breakpoints] save breakpoints via indexeddb and async-storage (#6741) Aug 6, 2018
.circleci migrate to CircleCi 2.0 (#6721) Jul 30, 2018
.github Fix broken link in (#6808) Aug 12, 2018
.vscode Transpile debugger modules for DevTools loader (#6220) May 7, 2018
_layouts Adding DocSearch to the site (#6022) Apr 19, 2018
assets Update suffix (#6827) Aug 14, 2018
bin [jest] Fix duplicate mock warning (#6723) Jul 30, 2018
configs [breakpoints] save breakpoints via indexeddb and async-storage (#6741) Aug 6, 2018
docs [breakpoints] save breakpoints via indexeddb and async-storage (#6741) Aug 6, 2018
flow-typed Add top-level await support (#6742) Aug 7, 2018
packages Fix expanding longString when the property is a getter. (#6785) Aug 15, 2018
src [QuickOpen] Don't repeat filename in subtitle for result list (#6836) Aug 15, 2018
.babelrc Cleanup babel (#4404) Oct 17, 2017
.editorconfig Add basic EditorConfig file. (#589) Aug 31, 2016
.eslintignore Transpile debugger modules for DevTools loader (#6220) May 7, 2018
.eslintrc Migrate source maps (#5824) Apr 23, 2018
.flowconfig [flow] add flow-typed libs + move to static immutable checks (#6518) Jun 21, 2018
.gitattributes Fix cross-configuration problems (#4475) Oct 25, 2017
.gitignore : Utilize Jest Runners for ESlint and Stylelint (#6293) May 15, 2018
.prettierignore Handle global-rewrite (Ember-related) original scope resolution (#5871) Apr 10, 2018
.remarkignore [parser] Test each set of fixtures across more build targets. (#6707) Jul 27, 2018
.remarkrc Fix remark (#2880) May 13, 2017
.stylelintignore update lint script to better capture directory layout (#2086) Feb 22, 2017
.stylelintrc [sync] backport changes from release-75 (#6702) Jul 26, 2018
.travis.yml [travis] bump mc sha (#6779) Aug 8, 2018
CODEOWNERS Add @juliandescottes to CODEOWNERS for properties file (#5488) Feb 21, 2018
Gemfile (WIP) Improve gh-pages (#1917) Feb 3, 2017
LICENSE License (#332) Jul 14, 2016 Move CoC and CONTRIBUTING (#6380) (#6436) May 30, 2018 Improve Issue triaging process (#5580) Mar 5, 2018
_config.yml (WIP) Improve gh-pages (#1917) Feb 3, 2017
jest-test.config.js Bump yarn.lock (#6730) Aug 1, 2018
jest.config.js Revert Jest Runners for linting and upgrade Jest to 23 🎉 (#6412) May 25, 2018
mocha-runner.html Update Mocha runner Jan 13, 2017
package.json Commit the auto-formatting down by yarn to the package.json (#6758) Aug 15, 2018
postcss.config.js Use mc help svg (#5942) Apr 17, 2018
wallaby.conf.js Add eslint rule for license header (#5973) Apr 14, 2018
webpack.config.js Improve Tab Accessibility (#6595) Jul 24, 2018
yarn.lock Add top-level await support (#6742) Aug 7, 2018


slack-badge npm-version PRs Welcome

debugger.html is a hackable debugger for modern times, built from the ground up using React and Redux. It is designed to be approachable, yet powerful. And it is engineered to be predictable, understandable, and testable.

Mozilla created this debugger for use in the Firefox Developer Tools. And we've purposely created this project in GitHub, using modern toolchains. We hope to not only to create a great debugger that works with the Firefox and Chrome debugging protocols but develop a broader community that wants to create great tools for the web.


Table of Contents

Quick Setup

Or take a look at our detailed getting started instructions.

curl -o- -L | bash -s
git clone

cd debugger.html
yarn start
# Go to http://localhost:8000

Next Steps

Getting Involved

This is an open source project and we would love your help. We have prepared a contributing guide to help you get started.

If this is your first PR or you're not sure where to get started, say hi in slack and a team member would be happy to mentor you.

We strive for collaboration with mutual respect for each other. Mozilla also has a set of participation guidelines which goes into greater detail specific to Mozilla employees and contributors.

Or, perhaps you have found a vulnerability in the debugger and want to report it? in that case, take a look at how we handle security bugs over, and open a bug at Bugzilla so we can track it while keeping users safe!

Development Guide

We strive to make the Debugger as development friendly as possible. If you have a question that's not answered in the guide, ask us in slack. We also ❤️ documentation PRs!

Themes theming changes for light, dark
Internationalization using or adding a localized string (l10n)
Prefs using or adding a preferences
Flow flow best practices and common gotchas
Logging tips for logging redux and client
Testing unit and integration test tips
Linting css, js, markdown linting
Configs how to use debugger settings locally
Hot Reloading steps for enabling hot reloading


Looking for a place to find our documentation? you can find them here!

Our Weekly updates are also posted!


Say hello in slack or in the #devtools-html channel on