Re: [Tails-dev] Tails 0.14 vs. iceweasel 10.0.9esr-1

Delete this message

Reply to this message
Autor: sajolida
Data:  
Para: The Tails public development discussion list
Tópicos Antigos: Re: [Tails-dev] Tails 0.14 vs. iceweasel 10.0.9esr-1
Assunto: Re: [Tails-dev] Tails 0.14 vs. iceweasel 10.0.9esr-1
On 29/10/12 15:46, intrigeri wrote:
> sajolida@??? wrote (29 Oct 2012 13:09:25 GMT) :
>> http://www.lalit.org/lab/javascript-css-font-detect/
>
>> This one uses the technique described above to check for a set of 23
>> common fonts.
>
>> Tails gets 9 fonts out of 33.
>> TBB gets 33 fonts out of 33, even though some of them are not installed
>> on the system.
>
>> My question is does this difference in behavior make sense?
>
> Not to my eyes.
>
>> Can it be related to any existing TBB patch?
>
> I'm not sure I get the question right, because both pieces of software
> under test are supposed to have the TorBrowser patches applied.
>
> I skimmed over the only obviously font-related patch, and as far as
> I understand it, it is not supposed to trigger such behaviour.
>
> I also had a quick look to see if an iceweasel patch was about fonts,
> and did not find any.
>
> My next bet would be to compare TBB's and Tails' Firefox configuration.


While doing that I found out that TBB had two font related preferences
that were not in Tails:

    pref("browser.display.max_font_attempts", 10);
    pref("browser.display.max_font_count", 5);


Those preferences activate the Torbrowser patch called
0011-Limit-the-number-of-fonts-per-document.patch. Adding them to
~/.mozilla/firefox/default/user.js removes the difference in results
from those two online fingerprint checks.

So, shall I add those to
config/chroot_local-includes/etc/iceweasel/profile/user.js, or maybe
there is a better place?