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Reviews for CanvasBlocker

CanvasBlocker by kkapsner

4.6 Stars out of 5
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361
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453 reviews
  • by Firefox user 14072583, 7 years ago
    Does not work according to fingerprint test at https://panopticlick.eff.org/

    Developer response

    posted 7 years ago
    What do you mean with "does not work"? Please open an issue at https://github.com/kkapsner/CanvasBlocker/issues where we can communicate better and therefore I can help better.
  • by ©®°˜, 7 years ago
    100% unique mean that is not really natural, canvas should not be unique but changed in order to be natural.
    Unique canvas fingerprints will do much worse.
    Is like you said you have a device that never exist.

    To better understand how this work :
    Google already have a full database with all kind of canvas signatures from all worldwide devices (iphone, android, computers, etc...), and if your canvas signature will not match on them database then you fail, it is a prove that your canvas is fake. If you try to spoof the signature then image pixel parameters will not match and again you fail so is almoust imposible to pass canvas.

    On default settings may make it pass the google test.

    For example google will not ask for SMS confirmation when a new gmail account is created because he trust the device you use.

    Most of people must understand why unique signatures is bad practice and all softwares that spoof parameters will make traking services to detect the device much easy

    Developer response

    posted 7 years ago
    Please open an issue at https://github.com/kkapsner/CanvasBlocker/issues where we can discuss this. AMOs rating comments are too limited to have a good conversation.

    One small comment on unique signatures: they are not bad by itself as long as they are not persistend (i.e. the timestamp you connect to the server is very likely to be a unique signature but it's not persistent). This is the case in the CB default settings.
  • by Firefox user 14039775, 7 years ago
  • by Firefox user 14037398, 7 years ago
  • by Firefox user 12808354, 7 years ago
    Works Fine
  • by Firefox user 13965824, 7 years ago
    It's doing it's job
  • by Firefox user 13954923, 7 years ago
    Excellent.
  • by Gummi, 7 years ago
    Can't seem to get version 0.4.4b working with Firefox ESR 52.7.2, there's just no icon visible anywhere on the UI.

    Edit: My bad! I remember that this addon had an icon before but nowadays it hasn't. Works great!

    Developer response

    posted 7 years ago
    This Addon does not have an icon that is always visible. Only a fingerprint icon is displayed in the adress bar when some canvas data was faked for the web page. You can test at http://kkapsner.github.io/CanvasBlocker/test/test.html

    If you still think that it's not working properly try version 0.4.4a and open a new issue at https://github.com/kkapsner/CanvasBlocker/issues

    EDIT: no problem. Glad that it works for you.
  • by Firefox user 13837360, 7 years ago
    Keep up the good work and thank you.
  • by Firefox user 13870378, 7 years ago
  • by Firefox user 13224783, 7 years ago
  • by Firefox user 13793914, 7 years ago
    Not good. Had partial protection before installing add-on. This add-on makes my browser 100% unique.

    Developer response

    posted 7 years ago
    Yes, in the standard settings of CB the fingerprint that is produced with CB is quite unique but not persistent. That means the browser itself (and therefore you) cannot be indentified by it. (The same issue was reportet on github: https://github.com/kkapsner/CanvasBlocker/issues/154 - if you want further informations you can explore the issues there or post a new one.)

    Also there are a lot of options which change the behaviour of CB (just mark the expert mode). If you want a less unique fingerprint you can use the "white" random number generator which will result in fingerprints similar to those of the Tor browser.
  • by Salsa, 7 years ago
  • by containers-everywhere, 7 years ago
  • by citizenserious, 7 years ago
  • by #98374, 7 years ago
  • by Firefox user 13730996, 7 years ago
    Hey there, take a look at Browser Console to know about your add-on's error. Keep up a good work.

    Developer response

    posted 7 years ago
    I do not see any errors. Please open an issue at https://github.com/kkapsner/CanvasBlocker/issues where you can describe the scenario when you see the errors.
  • by William, 8 years ago
  • by philrj, 8 years ago
  • by BRW, 8 years ago
    Perfect!!! Thanks!!!
  • by mibird, 8 years ago
    seemingly good help to browse with more privacy, complex work.
    since update from 17dec, blocks all web-pages :(

    Developer response

    posted 8 years ago
    I currently face weird problems. Please open an issue at https://github.com/kkapsner/CanvasBlocker/issues with all your details (versions, settings, etc.) so that I can find the root cause.

    EDIT: please try version 0.4.4
  • by Fred Thompson, 8 years ago
    Description claims there is a whitelist option but...there is no visible way to see, let alone edit, such a list.

    Developer response

    posted 8 years ago
    The whitelisting was hidden by the last release. You can whitelist by setting the desired blocking mode for the URL specifically. If you want to whitelist an URL just give it an "allow everything". You can still whitelist a site from the notifications. I should definitely clarify the description...

    Adding an URL specific block mode:
    go to options, click on the triangle next to the blocking mode, enter the domain you want to whitelist, click on the plus, now you can set the blocking mode for the domain.

    PS: you can still enter something in the white list by checking expert mode, open the export settings page and entering something in the whitelist field.

    EDIT: Is the screenshot of the settings not explanatory enough?
    EDIT2: It's easier for us to communicate on github. If you have any questions - just open an issue. Here the communication is slow and not relyable.

    EDIT3: please try version 0.4.4 - there the whitelist is available again.
  • by Registrierter Benutzer, 8 years ago
    reverted to 0.4.2 as 0.4.3 (all) is blocking pages, either when firefox starting with last session, or login to AMO

    Developer response

    posted 8 years ago
    Can you please file an issue at https://github.com/kkapsner/CanvasBlocker/issues with more details. I already know that there are problem but I'm not able to spot them because I never had a reproduction scenario.

    EDIT: Have you tried any of the Beta versions? https://github.com/kkapsner/CanvasBlocker/releases/
    EDIT: Please try version 0.4.4
  • by Firefox user 13600531, 8 years ago
    This is a fantastic add-on for users who are concerned about privacy while surfing the web because it efficiently detects and blocks/fakes canvas fingerprinting. I use CB on all my machines with Firefox (52-ESR and >57) and it supplements nicely other privacy-related add-ons. Based on my own experience, I can also confirm that it receives superb support by a very helpful and responsive developer. Clearly a must-have five-star addon!
  • by Firefox user 13567263, 8 years ago
    Funktioniert bei richtiger Einstellung korrekt. Schneller support. Danke!

    Works fine if settings are correct. Fast response. Thanks!

    Developer response

    posted 8 years ago
    I will look into this issue (progress can be seen here: https://github.com/kkapsner/CanvasBlocker/issues/161). The faking is working fine on https://browserleaks.com/canvas

    EDIT: They are using a very big canvas (400 000 pixels) to do the fingerprinting. It works fine if you disable the "Maximal fake size" ("Maximale Vortäuschgröße") setting. I will adjust the recommendation accordingly.