The official repository for the Thunderbird desktop email client.
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Filename Latest commit message Latest commit date
Release Engineering Landoscript 9be8af683b No Bug - Bumping Thunderbird l10n changesets r=release a=l10n-bump DONTBUILD
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2026-11-13 06:49:22 +00:00
.agents/skills Bug 2087687 - Add a Thunderbird code review LLM skill. r=aleca 2026-11-04 01:27:03 +00:00
.zed Bug 2060701 - Port Bug 2010106: Minor extensions to zed config. r=ebaginski 2026-08-05 23:11:34 +00:00
build Bug 2052824 - Trigger build. r=landing 2026-11-09 17:02:44 +00:00
calendar Bug 2058697 - Remove duplicated date/time fields in test data object. r=mkmelin 2026-11-12 22:22:49 +00:00
chat Bug 2086338 - Fix XMPP typing state reset when sending a message. r=freaktechnik 2026-11-06 18:50:58 +00:00
docs Bug 2092135 - Ignore axe contrast failures during CSS transitions. r=tobyp 2026-11-12 19:03:54 +00:00
mail No Bug - Bumping Thunderbird l10n changesets r=release a=l10n-bump DONTBUILD 2026-11-13 06:49:22 +00:00
mailnews Bug 2091761 - Preserve URL listeners for news requests without an explicit port. r=mkmelin 2026-11-12 22:22:50 +00:00
other-licenses/7zstub Bug 1840940 - Update Windows installer icon. r=aleca 2023-06-30 19:24:56 +02:00
python No bug - Archive completed Fluent migration scripts. rs=me DONTBUILD 2026-11-12 23:05:22 +00:00
rust Bug 2087631 - Use comm/rust/.cargo/audit.toml for cargo audit ignores. r=thunderbird-build-system-reviewers,coreycb,babolivier 2026-11-12 22:22:50 +00:00
suite No Bug - Update configs after merge day operations a=release 2026-11-05 19:20:03 +00:00
taskcluster Bug 2087631 - Use comm/rust/.cargo/audit.toml for cargo audit ignores. r=thunderbird-build-system-reviewers,coreycb,babolivier 2026-11-12 22:22:50 +00:00
testing Bug 2075468 - Port bug 2073844: Name the mozconfig of Thunderbird builds with the mozconfig key r=mkmelin 2026-09-27 22:11:07 +00:00
third_party Bug 1878375 - Synchronize vendored Rust libraries with mozilla-central. r=darktrojan 2026-11-10 04:22:42 +00:00
tools/lint Bug 2087631 - Use comm/rust/.cargo/audit.toml for cargo audit ignores. r=thunderbird-build-system-reviewers,coreycb,babolivier 2026-11-12 22:22:50 +00:00
.arcconfig Bug 2042254 - arcconfig: update to point to git phab repo r=dandarnell 2026-06-25 01:02:48 +00:00
.clang-format-ignore Bug 2023526 - Port bug 1670949: use clang-format as linter instead of its own command/job. r=sking 2026-03-17 16:14:30 -06:00
.cron.yml Bug 2087631 - Run a daily cargo audit of comm/rust/Cargo.lock. r=babolivier,coreycb 2026-11-03 10:08:00 +00:00
.editorconfig Bug 2060700 - Port Bug 2023419: Remove Emacs/Vim modelines to use .editorconfig. r=tobyp,sking 2026-08-05 23:11:34 +00:00
.gecko_rev.yml Bug 2028456 - Reset .gecko_rev.yml GECKO_HEAD_REF to default. 2026-07-02 11:26:31 +00:00
.gitattributes Bug 2052392 - Add .gitattributes file to Thunderbird repo. r=ebaginski DONTBUILD 2026-07-02 23:40:14 +00:00
.gitignore Bug 2067857 - Allow Cargo.toml.orig files for third party. DONTBUILD r=aleca 2026-08-31 18:08:06 +00:00
.hg-annotate-ignore-revs Bug 1936056 - Update .hg-annotate-ignore-revs. rs=me 2024-12-09 12:26:31 -05:00
.hgignore Bug 2060701 - Port Bug 2010106: Minor extensions to zed config. r=ebaginski 2026-08-05 23:11:34 +00:00
.hgtags No bug - tagging 3e9538cda6a985bb95c3cbf5dfa7e30bd9a776ed with NIGHTLY_153_END a=release DONTBUILD CLOSED TREE 2026-06-15 21:34:55 +00:00
.prettierignore Bug 2079158 - Rename SearchDialog.xhtml to searchDialog.xhtml. r=klamping 2026-10-15 05:09:08 +00:00
.prettierignore-css Bug 1968846 - Port bug 1606785: Enable prettier for CSS files. r=aleca 2025-12-08 14:06:12 +00:00
.prettierignore-non-css Bug 1968846 - Port bug 1606785: Enable prettier for CSS files. r=aleca 2025-12-08 14:06:12 +00:00
.readthedocs.yaml Bug 1908528 - Update Sphinx and dependencies. r=dandarnell 2024-10-01 13:53:02 +03:00
.stylelintignore Bug 2036665 - Add plumbing for built-in addons. r=coreycb 2026-06-16 11:44:39 +02:00
.stylelintrc.js Bug 2027759 - Enforce two colons for pseudo elements in CSS. r=aleca 2026-03-30 18:04:56 +01:00
.taskcluster.yml Bug 2046722 - Fix try-comm-central pushes with a task config. r=sking 2026-06-11 15:51:16 +12:00
.yamllint Bug 1793921 - Don't add local code as explicit dependency to storybook. r=rjl 2022-10-07 23:56:22 +00:00
.ycm_extra_conf.py Bug 1928027 - fix ycm_extra_conf.py according to ../mach commlint --fix. r=freaktechnik 2024-10-30 17:30:23 +00:00
AGENTS.md Bug 2085168 - Update JS documentation and frontend skills with various tweaks. r=aleca 2026-10-26 23:54:18 +00:00
AUTHORS Bug 1138689 - /me and /action should fire a sending-message notification before actually sending the action. r=clokep 2015-03-13 13:04:26 -07:00
CONTRIBUTING.md Bug 2076843 - Lint fix. rs=lint DONTBUILD 2026-10-06 08:37:18 +00:00
eslint-ignores.config.mjs Bug 2003041 - Port bug 2002659: Switch to @eslint/json for JSON linting. r=john.bieling 2025-11-28 18:20:54 +01:00
eslint.config.mjs Bug 2086287 - Port to Thunderbird: Switch from eslint-plugin-import to eslint-plugin-import-x. rs=bustage-fix DONTBUILD 2026-11-01 17:37:36 +00:00
mots.yaml Bug 2046768 - Add l10n reviewer group to governance docs. r=shtrom,tobyp 2026-06-12 16:41:19 -04:00
moz.build Bug 2023658 - Port bug 2023419 to Thunderbird - Remove Emacs/Vim modelines to use .editorconfig. r=tobyp 2026-06-02 15:13:40 -07:00
pyproject.toml Bug 1922252 - Rename tbxchannel to tb_l10n and update references. r=dandarnell,aleca 2024-10-10 22:49:51 +00:00
README.md Bug 2049881 - Update README to account for switch to Github. r=thunderbird-build-system-reviewers,ebaginski 2026-06-25 01:22:58 +00:00
review-context.toml Bug 2079973 - Add review-context.toml file to help with LLM assisted code reviews. r=sking 2026-10-19 17:23:02 +00:00

Thunderbird

Thunderbird is a powerful and customizable open source email client with many users. It is based on the same platform that Firefox uses.

Getting Started

This README will try and give you the basics that you need to get started, more comprehensive documentation is available on the Thunderbird Developer Website.

We also have documentation from this repository in a rendered version at Thunderbird Source Tree Documentation.

Mozilla Code Base

Thunderbird is built on the Mozilla platform, the same base that Firefox is built from. As such, the two projects share a lot of code and much of the documentation for one will apply to the other.

In order to be able to build Thunderbird - you will need the Firefox repository as well as the Thunderbird repository (where this README lives). Check out our Getting Started documentation for instructions on how and where to get the source code.

Firefox vs Thunderbird Source Code

The Firefox repository contains the Firefox codebase and all of the platform code. The Thunderbird repository is added as a subdirectory "comm/" under Firefox. This contains the code for Thunderbird.

Building Thunderbird

Follow the Building Thunderbird guide to get set up and build Thunderbird.

Contributing

Getting Plugged into the Community

We have a complete listing of the ways in which you can get involved with Thunderbird on our website. Below are some quick references from that page that you can use if you are looking to contribute to Thunderbird core right away.

Mailing Lists

If you want to participate in discussions about Thunderbird development, there are two main mailing lists you want to join.

  1. Thunderbird Planning: This moderated mailing list is for higher level topics like: the future of Thunderbird, potential features, and changes that you would like to see happen. It is also used to discuss a variety of broader issues around community and governance of the project.
  2. Thunderbird Developers: A moderated mailing list for discussing engineering plans for Thunderbird. It is a place where you can raise questions and ideas for core Thunderbird development.

Matrix Chat

If you want to ask questions about how to hack on Thunderbird, the Matrix room you want to join is #maildev:mozilla.org.

Report a Bug and Request Features

Thunderbird uses Bugzilla for reporting and tracking bugs. If you want to become a contributor to Thunderbird, you will need an account on Bugzilla.

Feature requests should be submitted to Mozilla Connect.

Fixing a Bug and Submitting Patches

See Fixing a Bug in the developer documentation.