Tor Browser 5.5a4 is released

by gk | November 4, 2015

A new alpha Tor Browser release is available for download in the 5.5a4 distribution directory and on the alpha download page.

This release features important security updates to Firefox.

Moreover, it comes with Tor and a number of other improvements. Most notably, we included Yan Zhu's fix for not leaking the Referer header when leaving a .onion domain and finally sorted out the HTTPS-Everywhere build problems allowing us to ship its latest version in our bundles again.

We fixed usability issues caused by our font fingerprinting patches and included a new defense against figerprinting users via available MIME types and plugins. Finally, besides additional minor bug fixes and clean-ups, we included an updated NoScript version.

Here is the complete changelog since 5.5a3:

  • All Platforms
    • Update Firefox to 38.4.0esr
    • Update Tor to
    • Update NoScript to
    • Update HTTPS-Everywhere to 5.1.1
    • Update Torbutton to
      • Bug 9623: Spoof Referer when leaving a .onion domain
      • Bug 16620: Remove old handling code
      • Bug 17164: Don't show text-select cursor on circuit display
      • Bug 17351: Remove unused code
      • Translation updates
    • Bug 17207: Hide MIME types and plugins from websites
    • Bug 16909+17383: Adapt to HTTPS-Everywhere build changes
    • Bug 16620: Move handling into a Firefox patch
    • Bug 17220: Support math symbols in font whitelist
    • Bug 10599+17305: Include updater and build patches needed for hardened builds
    • Bug 17318: Remove dead ScrambleSuit bridge
    • Bug 17428: Remove default Flashproxy bridges
    • Bug 17473: Update meek-amazon fingerprint
  • Windows
    • Bug 17250: Add localized font names to font whitelist
  • OS X
    • Bug 17122: Rename Japanese OS X bundle
  • Linux
    • Bug 17329: Ensure that non-ASCII characters can be typed (fixup of #5926)


Please note that the comment area below has been archived.

November 04, 2015


Oh, thanks a lot !!! Finally I can type directly in my native language in Tor Browser on Linux without the need to copy-past. That was kind of annoying tho. I appreciate your hard work on providing us such a wonderful web browser.

November 07, 2015


There is a large drop in flow rates with respect to the previous version ... It is simple comparing to Firefox 42 is flow divided by 10 while the previous version was only divided by 2 !
Does the price of success ?