Miscellaneous

4.1. How much does Privoxy slow my browsing down? This -has to add extra time to browsing.

How much of an impact depends on many things, including the CPU of the host system, how aggressive the configuration is, which specific actions are being triggered, @@ -98,8 +101,8 @@ CLASS="APPLICATION" >Privoxy itself for each page, is relatively small in the overall scheme of things, and happens very quickly. This is typically - more than offset by time saved not downloading and rendering ad images (if ad - blocking is being used).

deanimate-gifs - actions will certainly cause a perceived slowdown, since the entire document - needs to be buffered before displaying. And on very large documents, filtering may have - some measurable impact. How much depends on the page size, the actual - definition of the filter(s), etc. See below. Most other actions have little - to no impact on speed.

- Also, when filtering is enabled, typically there is a disabling of - compression, (see

Also, when filtering is enabled but zlib support isn't available, compression + is often disabled (see prevent-compression). - This can have an impact on speed as well. Again, the page size, etc. will - determine how much of an impact.

4.2. I notice considerable -delays in page requests compared to the old Junkbuster. What's wrong?

If you use any only knows how to differentiate filterable content because of the MIME type as reported by the server, or because of some configuration setting that enables/disables - filtering.

4.3. What are "http://config.privoxy.org/" and -"http://p.p/"? web site at config.privoxy.org. With recent versions of Privoxy (version 2.9.x and - later), the user interface features information on the run time status, the - configuration, and even a built-in editor for the actions files. Note that the built-in URLs from earlier versions of Junkbuster - / Privoxy, http://example.com/show-proxy-args and http://i.j.b/, - are no longer supported. If you still use such an old version, you should really consider - upgrading to 3.0.6.

4.4. How can I submit new ads, or report -problems?Please see the 4.5. If I do submit missed ads, will -they be included in future updates? Whether such submissions are eventually included in the 4.6. Why doesn't anyone answer my support -request? Rest assured that it has been read and considered. Why it is not answered, could be for various reasons, including no one has a good answer for it, no @@ -340,8 +320,8 @@ CLASS="SECT2" CLASS="SECT2" >4.7. How can I hide my IP address?4.7. How can I hide my IP address? If you run both the browser and However, these proxies are called "anonymous" because you don't need - a password, not because they would offer any real anonymity. + to authenticate, not because they would offer any real anonymity. Most of them will log your IP address and make it available to the authorities in case you violate the law of the country they run in. In fact you can't even rule out that some of them only exist to *collect* information on (those suspicious) people with a more than average preference for privacy. Your best bet is to chain If you want to hide your IP address from most adversaries, + you should consider chaining Privoxy with Tor, - an EFF supported onion routing system. +>. The configuration details can be found in How do I use Privoxy together with together + with Tor section 4.8. Can Privoxy guarantee I am anonymous? 4.8. Can Privoxy guarantee I am anonymous? No. Your chances of remaining anonymous are greatly improved, but unless you +> No. Your chances of remaining anonymous are improved, but unless you Tor - or a similar system and know what you're doing when it comes to configuring - the rest of your system, it would be safest to assume that everything you do + or a similar proxy and know what you're doing when it comes to configuring + the rest of your system, you should assume that everything you do on the Web can be traced back to you. you more freedom to decide which sites +> more freedom to decide which sites you can trust, and what details you want to reveal. But it neither hides your IP address, nor can it guarantee that the rest of the system behaves correctly. There are several possibilities how a web sites can find @@ -443,7 +420,7 @@ CLASS="APPLICATION" > Most of Privoxy's protection can be easily subverted +> privacy-enhancing features can be easily subverted by an insecure browser configuration, therefore you should use a browser that can be configured to only execute code from trusted sites, and be careful which sites you trust. For example there is no point in having 4.9. A test site says I am not using a Proxy. 4.9. A test site says I am not using a Proxy. Good! Actually, they are probably testing for some other kinds of proxies. Hiding yourself completely would require additional steps. 4.10. How do I use Privoxy - together with Tor? Before you configure Privoxy to use Tor - ( to use + http://tor.eff.org/), +>Tor, please follow the User Manual If it is, refer to Tor's extensive documentationTor - to increase your anonymity level, therefore you should use socks4a, - to make sure Privoxy's DNS requests are + to increase your anonymity level, therefore you should use socks4a, to make sure DNS requests are done through Tor This is enough to reach the Internet, but additionally you should +> This is enough to reach the Internet, but additionally you might want to uncomment the following forward rules, to make sure your local network is still reachable through Privoxy: Unencrypted connections to systems in these address ranges will be as (un)secure as the local network is, but the alternative is - that you can't reach the network at all. - If you also want to be able to reach servers in your local - network by using their names, you will need additional - exceptions that look like this: If you want your browser to be able to reach servers in your local + network by using their names, you will need additional exceptions + that look like this: Tor Faq 4.2Tor does, why it is no replacement for - application level security, and why you shouldn't use it for unencrypted logins. 4.11. Might some things break because header information or -content is being altered? Definitely. It is common for sites to use browser type, browser version, HTTP header content, and various other techniques in order to dynamically @@ -737,16 +712,13 @@ content is being altered? The "User-Agent" is often used in this way to identify - the browser, and adjust content accordingly. Changing this now (at least not - further than removing the OS information) is not recommended, since so many - sites do look for it. You may get undesirable results by changing just this - one aspect. is sometimes used in this way to identify + the browser, and adjust content accordingly. Also, different browsers use different encodings of Russian and Czech +> Also, different browsers use different encodings of non-English characters, certain web servers convert pages on-the-fly according to the User Agent header. Giving a "Referer" or cookie is provided, is another example. (But you can forge both headers without giving information away). There are - many other ways things that can go wrong when trying to fool a web server. The + many other ways things can go wrong when trying to fool a web server. The results of which could inadvertently cause pages to load incorrectly, partially, or even not at all. And there may be no obvious clues as to just what went wrong, or why. Nowhere will there be a message that says @@ -796,21 +768,26 @@ CLASS="SECT2" > 4.12. Can Privoxy act as a "caching" proxy to -speed up web browsing? No, it does not have this ability at all. You want something like Squid for this. And, yes, - before you ask, or + Polipo for this. + And, yes, before you ask, Privoxy can co-exist @@ -835,17 +812,17 @@ CLASS="SECT2" > 4.13. What about as a firewall? Can Privoxy protect me? 4.13. What about as a firewall? Can Privoxy protect me? Not in the way you mean, or in the way a true firewall can. +> Not in the way you mean, or in the way some firewall vendors claim they can. Privoxy can help protect your privacy, but not - protect you from intrusion attempts. It is, of course, perfectly possible - and recommended to use can help protect your privacy, but can't + protect your system from intrusion attempts. It is, of course, perfectly possible + to use 4.14. I have large empty spaces / a checkerboard pattern now where -ads used to be. Why? It is technically possible to eliminate banners and ads in a way that frees their allocated page space. This could easily be done by blocking with @@ -897,9 +874,9 @@ CLASS="SECT2" > 4.15. How can Privoxy filter Secure (HTTPS) URLs? 4.15. How can Privoxy filter Secure (HTTPS) URLs? Since secure HTTP connections are encrypted SSL sessions between your browser and the secure site, and are meant to be reliably 4.16. Privoxy runs as a "server". How -secure is it? Do I need to take any special precautions? There are no known exploits that might affect - Privoxy. On Unix-like systems, - On Unix-like systems, Privoxy can run as a non-privileged - user, which is how we recommend it be run. Also, by default + user, which is how we recommend it be run. Also, by default Privoxy only listens to requests - from listens to requests from "localhost" only. The server aspect of - + only. The server aspect of Privoxy is not itself directly exposed to the - Internet in this configuration. If you want to have +> is not itself directly + exposed to the Internet in this configuration. If you want to have Privoxy4.17. How can I temporarily disable Privoxy?4.17. Can I temporarily disable Privoxy? The easiest way is to access Privoxy with your - browser by using the remote toggle URL: doesn't have a transparent proxy mode, + but you can toggle off blocking and content filtering. The easiest way to do that is to point your browser + to the remote toggle URL: http://config.privoxy.org/toggle. - See the . See the Bookmarklets sectionUser Manual for an easy way to access this - feature. config file. 4.18. When "disabled" is Privoxy totally -out of the picture? No, this just means all filtering and actions are disabled. +> No, this just means all optional filtering and actions are disabled. Privoxy is still acting as a proxy, but just not - doing any of the things that is still acting as a proxy, but just + doing less of the things that Privoxy would @@ -1073,8 +1054,8 @@ CLASS="SECT2" CLASS="SECT2" >4.19. How can I tell Privoxy to totally ignore certain sites?4.19. How can I tell Privoxy to totally ignore certain sites? Bypassing a proxy, or proxying based on arbitrary criteria, is purely a browser configuration issue, not a 4.20. My logs show Privoxy "crunches""crunch"?? A "crunch". Since version 3.0.7, Privoxy will also log the crunch reason. + If you are using an older version you might want to upgrade. 4.21. Can Privoxy effect files that I download -from a webserver? FTP server? From the webserver's perspective, there is no difference between viewing a document (i.e. a page), and downloading a file. The same is true of @@ -1193,7 +1177,7 @@ CLASS="APPLICATION" > knows the differences in files according to the "Document Type""Content Type" as reported by the webserver. If this is reported accurately (e.g. In short, filtering is "ON" if a) the Document Type as reported +> if a) the content type as reported by the webserver is appropriate "bad". It's the configuration that let's it all happen or not. . It's the configuration that lets it all happen or not. If you download text files, you probably do not want these to be filtered, particularly if the content is source code, or other critical content. Source @@ -1270,7 +1254,7 @@ CLASS="EMPHASIS" CLASS="APPLICATION" >Privoxy does not do FTP at all, only HTTP - and HTTPS (SSL) protocols, so please don't try. 4.22. I just downloaded a Perl script, and Privoxy -altered it! Yikes, what is wrong! Please read above. 4.23. Should I continue to use a "HOSTS" file for ad-blocking? file for ad-blocking? One time-tested technique to defeat common ads is to trick the local DNS system by giving a phony IP address for the ad generator in the local @@ -1323,8 +1307,8 @@ CLASS="APPLICATION" CLASS="FILENAME" >HOSTS file, in fact, not only - duplicates effort, but may get in the way. It is recommended to remove - such entries from your HOSTS file. If you think @@ -1361,9 +1345,9 @@ CLASS="SECT2" CLASS="SECT2" >4.24. Where can I find more information about Privoxy -and related issues? Other references and sites of interest to http://sourceforge.net/projects/ijbswa/https://sourceforge.net/projects/ijbswa/, the Project Page for http://sourceforge.net/tracker/?group_id=11118&atid=460288https://sourceforge.net/tracker/?group_id=11118&atid=460288, to submit "misses" - - http://privacy.net/, a useful site - to check what information about you is leaked while you browse the web. +>http://www.squid-cache.org/, a popular + caching proxy, which is often used together with Privoxy. http://www.squid-cache.org/, a very popular - caching proxy, which is often used together with http://www.pps.jussieu.fr/~jch/software/polipo/, + Privoxy. +>Polipo is a caching proxy with advanced features + like pipelining, multiplexing and caching of partial instances. In many setups + it can be used as Squid replacement. http://tor.eff.org/https://www.torproject.org/, 4.25. I've noticed that Privoxy changes "Microsoft""MicroSuck"! Why are you manipulating my browsing?! Why are you manipulating my browsing? We're not. The text substitutions that you are seeing are disabled in the default configuration as shipped. You have either manually @@ -1659,11 +1649,34 @@ CLASS="QUOTE" >"Text replacements for subversive browsing fun!" or you are using an older Privoxy version and have implicitly - activated it by choosing the "Adventuresome""Advanced" profile in the - web-based editor. Please upgrade! 4.26. Does Privoxy produce "valid" HTML (or XHTML)? Privoxy generates HTML in both its own "templates", and possibly + whenever there are text substitutions via a Privoxy filter. While this + should always conform to the HTML 4.01 specifications, it has not been + validated against this or any other standard.