New Alpha Release: Tor Browser 15.0a2

[system]

by ma1 | September 1, 2025

Tor Browser 15.0a2 is now available from the Tor Browser download page and also from our distribution directory.

This version includes important security updates to Firefox.

Thanks to WhyNotHugo for fixing the "Contributing" link in our README file.

Send us your feedback

If you find a bug or have a suggestion for how we could improve this release, please let us know.

Full changelog

The full changelog since Tor Browser 15.0a1 is:

• All Platforms
  • Updated NoScript to 13.0.9
  • Updated OpenSSL to 3.5.2
  • Bug tor-browser#43727: Update moz-toggle customisation for ESR 140
  • Bug tor-browser#43832: Drop eslint-env
  • Bug tor-browser#43864: Remove features from the unified search button
  • Bug tor-browser#44045: Drop AI and machine learning components
  • Bug tor-browser#44048: Backport Bug 1979608
  • Bug tor-browser#44069: Update meek-azure related strings to meek
  • Bug tor-browser#44094: Rebase Tor Browser alpha onto 140.2.0esr
  • Bug tor-browser#44100: Backport Security Fixes from Firefox 142
  • Bug tor-browser#44140: Align PDF changes to 140esr
  • Bug tor-browser-build#41442: Update our audit CSVs to use the new Audit template
• Windows + macOS + Linux
  • Updated Firefox to 140.2.0esr
  • Bug tor-browser#43111: Delete our webextensions for search engines when Bug 1885953 is fixed upstream
  • Bug tor-browser#43519: Replace tor-loading.png with SVG
  • Bug tor-browser#43525: Check if our search engine customization still works after ESR 140 transition
  • Bug tor-browser#43728: Update search engine icon sizes
  • Bug tor-browser#43795: Restore the URL classifier XPCOM components.
  • Bug tor-browser#43817: Write e2e test for verifying if the browser is connected to the Tor network
  • Bug tor-browser#43844: Security level shield icon should be flipped for RTL locales
  • Bug tor-browser#43874: Incorporate our unified extension button hiding logic into mozilla's changes for ESR 140
  • Bug tor-browser#43901: Modify about:license for Tor Browser and drop about:rights
  • Bug tor-browser#43902: Hide Sidebar buttons
  • Bug tor-browser#43903: Report broken site is disabled rather than hidden
  • Bug tor-browser#44030: Security Level selector does not get confirmation before restarting
  • Bug tor-browser#44034: Update string used for checkbox on New Identity confirmation dialog
  • Bug tor-browser#44040: Modify nsIPrompt and the commonDialog code to allow destructive buttons
  • Bug tor-browser#44041: Letterboxing causes greyed out alert background to be mis-aligned
  • Bug tor-browser#44090: Several of our XUL pages cause a crash because of missing CSP
  • Bug tor-browser#44095: Rename connectionPane.xhtml and remove it from the jar
  • Bug tor-browser#44106: Make sure background tasks are not used for shutdown cleanup
  • Bug tor-browser#44115: Make remove all bridges dialog use a destructive red button
  • Bug tor-browser#44125: Do not offer to save signatures by default in Private Browsing Mode
• Windows + Android
  • Bug tor-browser#44062: Force touch enabled on Windows and Android
• Windows
  • Bug tor-browser#44046: Replace BASE_BROWSER_UPDATE with BASE_BROWSER_VERSION in the font visibility list
• macOS
  • Bug tor-browser#44127: Do not show macOS Privacy hint on network error pages
• Android
  • Updated GeckoView to 140.2.0esr
  • Bug tor-browser#43179: Make persistent 'private tabs' notification distinct from Firefox's
  • Bug 43346: Remove the "[android] Stop PrivateNotificationService" patch [tor-browser]
  • Bug tor-browser#43645: Swiping away doesn't always disconnect from tor
  • Bug tor-browser#43699: Dummy "about:" pages are not cleared from recently closed tabs (and possibly elsewhere) because they are normal tabs, not private tabs.
  • Bug tor-browser#43826: Review Mozilla 1960122: Use MOZ_BUILD_DATE in Fenix build configuration
  • Bug tor-browser#44021: Android settings page colors are sometimes messed up (seems to be on the first launch)
  • Bug tor-browser#44042: Debug crash when opening settings too quickly after launching app
  • Bug tor-browser#44047: Tor Browser's home doesn't have the background at the first load on Android
  • Bug tor-browser#44081: Swiping away the "private tabs" notification requires rebootstrapping.
  • Bug tor-browser#44083: "snowflake" is lower case on Android
  • Bug tor-browser#44098: Bookmarks offer a way to go to sync in 15.0a1
  • Bug tor-browser#44139: Restore the (inactive) YouTube and Reddit search plugins on Android
• Build System
  • All Platforms
    • Bug tor-browser#44061: "Contributing" link is broken
    • Bug tor-browser#44067: Move --enable-geckodriver only to Linux-only mozconfigs
    • Bug tor-browser#44103: git's export-subst is a reproducibility problem
    • Bug tor-browser#44104: Don't run linter when there are no overall changes
    • Bug tor-browser-build#26408: Make MAR signature checks clearer when creating incremental MAR files
    • Bug tor-browser-build#40551: Drop go reproducibility patches
    • Bug tor-browser-build#40697: Delete repackage_browser.sh
    • Bug tor-browser-build#40698: Update locale in tbb_version.json
    • Bug tor-browser-build#41517: Add morgan's key to the setup account on the signing machine
    • Bug tor-browser-build#41522: Adapt our signing scripts to be able to sign the VPN app
    • Bug tor-browser-build#41534: Copy geckodriver only for Linux x86-64
    • Bug tor-browser-build#41537: Add script to count mar downloads from web logs
    • Bug tor-browser-build#41539: Update Ubuntu version used to run mmdebstrap to 24.04.3
    • Bug rbm#40087: Downloaded files getting stricter permissions than expected
  • Windows + Linux + Android
    • Updated Go to 1.24.6
  • macOS
    • Bug tor-browser-build#41527: Update libdmg-hfsplus and enable LZMA compression on dmgs
    • Bug tor-browser-build#41538: Bump macOS SDK to 15.5
  • Android
    • Bug tor-browser#44078: Modify ./autopublish-settings.gradle for building a-s and glean with uniffi-bindgen no-op
    • Bug tor-browser-build#41523: Use custom built Glean package on Android
    • Bug tor-browser-build#41531: Update relprep.py script to handle application-services updates
    • Bug tor-browser-build#41548: Hide tor's symbols on Android and add other linker options to save space

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This is a companion discussion topic for the original entry at https://blog.torproject.org/new-alpha-release-tor-browser-150a2