[tor-bugs] #13858 [Tor Browser]: Resolution fingerprinting possible with Tor Browser Bundle

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#13858: Resolution fingerprinting possible with Tor Browser Bundle
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     Reporter:  sleurn       |      Owner:  tbb-team
         Type:  defect       |     Status:  new
     Priority:  major        |  Milestone:
    Component:  Tor Browser  |    Version:
   Resolution:               |   Keywords:
Actual Points:               |  Parent ID:
       Points:               |
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Comment (by sleurn):

 Replying to [comment:2 gk]:
 > The values are hard-coded to a multiple of 200x100. That is unless you
 start resizing your screen. Are you doing that?

 No, I don't. The above was with its window maximized. (I.e. not the
 default window size it starts up with on first run after unpacking into a
 new directory, which is smaller, but the one resulting from using the
 "maximize" window button.)

 My usage scenario is:
 - Download the new TBB version
 - Delete the old "Tor Browser" folder
 - Unpack the new version into the same directory as the old one. (I.e.,
 re-creating the "Tor Browser" folder. Which, though, is not on the
 desktop.)
 - On first run:
         - Using the NoScript button, "Forbid scripts globally"
         - Hide the menu bar
         - In the browser options -> Advanced -> General, disable "Use
 smooth scrolling"

 For the "panopticlick" test I did the "Temporarily allow all this page"
 with the NoScript button. Since resolution detection requires javascript.

 But you are right that it changes when resized, e.g., I made it
 significantly smaller and got 622x296x24 (same version on WinXP).

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/13858#comment:3>
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