New Alpha Release: Tor Browser 13.0a3 (Android, Windows, macOS, Linux)

by richard | August 24, 2023

Tor Browser 13.0a3 is now available from the Tor Browser download page and also from our distribution directory.

This release updates Firefox to 115.2.0esr, including bug fixes, stability improvements and important security updates. Android-specific security updates from Firefox 117 are not yet available, but will be part of the next alpha release scheduled in two weeks.

Major Changes

This is our third alpha release in the 13.0 series which represents a transition from Firefox 102-esr to Firefox 115-esr. This builds on a year's worth of upstream Firefox changes, so alpha-testers should expect to run into issues. If you find any issues, please report them on our gitlab or on the Tor Project forum.

We are in the middle of our annual esr transition audit, where we review Mozilla's year's worth of work with an eye for privacy and security issues that would negatively affect Tor Browser users. This will be completed before we transition the 13.0 alpha series to stable. At-risk users should remain on the 102-esr based 12.5 stable series which will continue to receive security updates until 13.0 alpha is promoted to stable.

Build System

We have made the naming scheme for all of our build outputs mutually consistent! This basically means that going forward all our build artifacts will have a name following the form ${ARTIFACT}-${OS}-${ARCH}-${VERSION}.${EXT}. For example, in 13.0a2 the macOS .dmg pakage was named TorBrowser-13.0a2-macos_ALL.dmg whereas in 13.0a3 it is named tor-browser-macos-13.0a3.dmg.

If you are a downstream packager or in some other way download Tor Browser artifacts in scripts or automation, you will have a bit more work to do beyond bumping the version number once the 13.0 alpha stabilizes.

Known Issues


Building generated debug headers are not currently reproducible. This only affects debug info and does not affect users. This issue is being tracked here. It will either be fixed before the 13.0 alpha series transitions to stable later this year, or we will disable this developer feature by default to ensure fully matching builds.


There are various graphical bugs in the bootstrapping and landing pages in Tor Browser for Android including misaligned text and Firefox branding. The Tor Browser onboarding for first-time users is also missing. These issues (among others) are being tracked here, here and here.

Full changelog

We would like to thank volunteer contributor cypherpunks1 for their fixes for tor-browser#40175, and tor-browser#41642. If you would like to contribute, our issue tracker can be found here.

The full changelog since Tor Browser 13.0a2 is:


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