FireFox browser stores readable thumbnails [SOLVED]

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Barkin
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Joined: Fri 12 Aug 2011, 04:55

FireFox browser stores readable thumbnails [SOLVED]

#1 Post by Barkin »

I only just noticed this issue, apparently it's been known for about six months ... http://www.zdnet.com/blog/security/firefox-thumbnails-could-expose-private-data-fix-coming-soon/12568

2012 releases of FireFox browser store thumbnails of webpages you've visited which have sufficient resolution to allow possibly sensitive data to be read from these thumbnail-screenshots.

The thumbnails are big by thumbnail standards : some are over 60kB (.png), one is attached, most of the text is readable if you enlarge the image ...
Attachments
FireFox big ''thumbnail'', the text is just readable.png
FireFox thumbnail (screenshot)
(23.76 KiB) Downloaded 1378 times
Last edited by Barkin on Mon 19 Nov 2012, 23:30, edited 1 time in total.

postfs1

Re: FireFox browser stores readable thumbnails (screenshots)

#2 Post by postfs1 »

Firefox ---> MENU ---> Edit/Preferences/Content: [ EMPTY ] Load images automatically [[ Exceptions... ]]

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Barkin
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Re: FireFox browser stores readable thumbnails (screenshots)

#3 Post by Barkin »

postfs1 wrote:Firefox ---> MENU ---> Edit/Preferences/Content: [ EMPTY ] Load images automatically [[ Exceptions... ]]

That won't stop the screenshot "thumbnails" from being displayed when "NewTab" is selected in FireFox,
nor does it prevent these screenshot images being saved in the FireFox folder on the computer.

Nor does the "fix" suggested by mozilla ...
Mozilla.org wrote:If you are concerned about your privacy, you can turn this feature off completely:

In the Location bar, type about:config and press EnterReturn.
The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise!, to continue to the about:config page.
Type browser.newtab.url in the search box.
Double-click the browser.newtab.url preference and change the url from about:newtab to about:blank. Alternately, you can change it to about:home for the Firefox Google home page, or type in your preferred home page, for example google.com.
Click OK and close the about:config tab.
http://support.mozilla.org

Doing as Mozilla suggest does stop the screenshot "thumbnails" from being displayed in the browser, but they still exist and accumulate in the FireFox thumbnail folder.

postfs1

Re: FireFox browser stores readable thumbnails (screenshots)

#4 Post by postfs1 »

postfs1 wrote:Firefox ---> MENU ---> Edit/Preferences/Content: [ EMPTY ] Load images automatically [[ Exceptions... ]]
(by the way, now i have an opportunity to watch YOUTUBE.COM without NVIDIA PROPRIETARY DRIVER)
plus

Firefox ---> MENU ---> Edit/Preferences/Advanced/Network: Offline storage: Use up to [ 0 ] MB of space for the cache

If there is NO GOOD RESULT, then:

Firefox ---> MENU ---> Edit/Preferences/Content: Fonts&Colors: SMALLEST FONTS(perhaps not standard, and also, not those fonts, which the page is waiting)
In such a case: Firefox ---> MENU ---> View ---> Zoom ---> ...


Note: the work what has been done here is just for creation of the approximate scheme, because there was no access to fresh version of web browser.
Last edited by postfs1 on Fri 23 Nov 2012, 01:05, edited 4 times in total.

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Barkin
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#5 Post by Barkin »

So far the only solution I have found is to have FireFox delete all history when the browser is closed. The FireFox thumbnail folder is cleared along with history.

But I'd prefer to keep history, I'd just like the option of not having the screenshot-thumbnails saved, ( which could contain sensitive data like bank card numbers, emails, etc ).

Within Puppy it may be possible to symlink the FireFox screenshot-thumbnail directory to the tmp (temporary) directory, so the screenshot-thumbnails are deleted on shutdown. (whilst retaining history).

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Barkin
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#6 Post by Barkin »

If you're on Windows and have got CCleaner apparently there's a fix ... http://forum.piriform.com/index.php?showtopic=36927&view=findpost&p=222297

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puppy_apprentice
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#7 Post by puppy_apprentice »

try to add new option to firefox config:

in address bar write:

Code: Select all

about:config
and add this option as boolean (New->Boolean):

Code: Select all

browser.pagethumbnails.capturing_disabled
and set it to true, restart firefox

maybe will works and don't make new webshots

for more info chceck via google: "browser.pagethumbnails.capturing_disabled" or "about:config"

2byte
Posts: 353
Joined: Mon 09 Oct 2006, 18:10

#8 Post by 2byte »

Thanks puppy_apprentice

browser.pagethumbnails.capturing_disabled works after clearing the cache and restarting Firefox.

A new tab page still showed the picture squares with the web sites listed beneath. To turn those off, and also get rid of the 9 little squares at the top right of the blank page, I did this

about:config

Search for -- browser.newtab.url

Change the value (url) from about:newtab to about:blank


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Barkin
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#9 Post by Barkin »

puppy_apprentice wrote:... add this option as boolean (New->Boolean):

Code: Select all

browser.pagethumbnails.capturing_disabled
and set it to true, restart firefox
Thanks puppy_apprentice that fixed it for me.
puppy_apprentice wrote: maybe will works and don't make new webshots
The Firefox high-resolution screenshots thumbnail folder remains empty after I deleted its contents :D
Attachments
location of firefox high-res screenshot-thumbnails in Puppy Linux.png
The location of the Firefox high-resolution screenshot "thumbnails" in Puppy Linux
(12.81 KiB) Downloaded 1111 times

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puppy_apprentice
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#10 Post by puppy_apprentice »

2byte wrote: Search for -- browser.newtab.url

Change the value (url) from about:newtab to about:blank
or u could prepare own html page (simple portal) with favorite links (like Barry's Blog, this forum etc.) and/or search form with multiple search options and change <url> to eg. path/mynewtab.html

some info to make own multiple search form:
http://www.infolink.org/engine/
http://www.mediacollege.com/internet/ja ... earch.html

Bligh
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Location: California

#11 Post by Bligh »

My FF does not store tn's. I always set history and cache to zero. It does not save pw's either.
Cheers

Bligh
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Joined: Sun 08 Jan 2006, 11:05
Location: California

#12 Post by Bligh »

The thread is marked (solved) what did you do to solve the issue ?
Cheers

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Barkin
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#13 Post by Barkin »

Bligh wrote:... what did you do to solve the issue ?
I applied Puppy_apprentice's solution ... http://www.murga-linux.com/puppy/viewtopic.php?p=665584#665584
which requires adding a line to FireFox's config(uration).

Then I deleted the contents of the Firefox thumbnail folder.

So I still retain browsing history, but don't have giant readable screenshot thumbnails.

Bligh
Posts: 480
Joined: Sun 08 Jan 2006, 11:05
Location: California

#14 Post by Bligh »

Thanks, I may try that.
Cheers

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