+
+<sect1 id="misc"><title>Miscellaneous</title>
+
+<sect2 renderas="sect3">
+<title id="slowsme">How much does <application>Privoxy</application> slow my browsing down? This
+has to add extra time to browsing.</title>
+<para>
+ It should not slow you down any in real terms, and may actually help
+ speed things up since ads, banners and other junk are not being displayed.
+ The actual processing time required by <application>Privoxy</application>
+ 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.
+</para>
+
+<para>
+ <quote>Filtering</quote> content via the <literal><ulink
+ url="../user-manual/actions-file.html#FILTER">filter</ulink></literal> or
+ <literal><ulink
+ url="../user-manual/actions-file.html#DEANIMATE-GIFS">deanimate-gifs</ulink></literal>
+ actions may cause a perceived slowdown, since the entire document needs to be buffered
+ before displaying. See below.
+</para>
+
+</sect2>
+
+
+<sect2 renderas="sect3" id="loadingtimes"><title>I noticed considerable
+delays in page requests compared to the old Junkbuster. What's wrong?</title>
+<para>
+ If you use any <literal><ulink
+ url="../user-manual/actions-file.html#FILTER">filter</ulink></literal> action,
+ such as filtering banners by size, web-bugs etc, or the <literal><ulink
+ url="../user-manual/actions-file.html#DEANIMATE-GIFS">deanimate-gifs</ulink></literal>
+ action, the entire document must be loaded into memory in order for the filtering
+ mechanism to work, and nothing is sent to the browser during this time.
+</para>
+<para>
+ The loading time does not really change in real numbers, but the feeling is
+ different, because most browsers are able to start rendering incomplete
+ content, giving the user a feeling of "it works". This effect is especially
+ noticeable on slow dialup connections.
+ </para>
+</sect2>
+
+
+<sect2 renderas="sect3" id="configurl"><title>What are "http://config.privoxy.org/" and
+"http://p.p/"?</title>
+<para>
+ <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink> is the
+ address of <application>Privoxy</application>'s built-in user interface, and
+ <ulink url="http://p.p/">http://p.p/</ulink> is a shortcut for it.
+</para>
+<para>
+ Since <application>Privoxy</application> sits between your web browser and the Internet,
+ it can simply intercept requests for these addresses and answer them with its built-in
+ <quote>web server</quote>.
+</para>
+<para>
+ This also makes for a good test for your browser configuration: If entering the
+ URL <ulink url="http://config.privoxy.org/">http://config.privoxy.org/</ulink>
+ takes you to a page saying <quote>This is Privoxy..</quote>, everything is OK.
+ If you get a page saying <quote>Privoxy is not working</quote> instead, then
+ your browser didn't use <application>Privoxy</application> for the request,
+ hence it could not be intercepted, and you have accessed the <emphasis>real</emphasis>
+ web site at config.privoxy.org.
+</para>
+<para>
+ With recent versions of <application>Privoxy</application> (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 <ulink
+ url="../user-manual/actions-file.html">actions files</ulink>.
+</para>
+
+<para>
+ Note that the built-in URLs from earlier versions of <application>Junkbuster</application>
+ / <application>Privoxy</application>, 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 &p-version;.
+</para>
+</sect2>
+
+<!--
+FIXME: commented out until we have data. HB 03/18/02.
+
+<sect2 renderas="sect3" id="badfiledesc"><title>I get the message 'Bad File Descriptor', why?</title>
+<para>
+ Fill me.
+</para>
+</sect2>
+
+-->
+
+<sect2 renderas="sect3" id="blocklist"><title>Do you still maintain the blocklists?</title>
+ <para>
+ No. The patterns for blocking now reside (among other things) in the <ulink
+ url="../user-manual/actions-file.html">actions files</ulink>, which are
+ actively maintained instead. See next question ...
+</para>
+</sect2>
+
+<sect2 renderas="sect3" id="newads"><title>How can I submit new ads?</title>
+<para>
+Yes, absolutely! Please see the <link linkend="contact">Contact section</link> for
+how to do that. Please note that you (technically) need the latest
+<application>Privoxy</application> version for this to work.
+</para>
+
+</sect2>
+
+<sect2 renderas="sect3" id="ip"><title>How can I hide my IP address?</title>
+<para>
+ If you run both the browser and the proxy locally, you cannot hide your IP
+ address with <application>Privoxy</application> or any other software. The
+ server needs to know your IP address to send the answers back to you.
+</para>
+<para>
+ Fortunately there are many publicly usable anonymous proxies out there, which
+ solve the problem by providing a further level of indirection between you and
+ the web server, shared by many people, and thus letting your requests "drown"
+ in white noise of unrelated requests as far as user tracking is concerned.
+</para>
+<para>
+ Most of them will, however, log your IP address and make it available to the
+ authorities in case you abuse that anonymity for criminal purposes. 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.
+</para>
+<para>
+ You can find a list of anonymous public proxies at <ulink
+ url="http://www.multiproxy.org/anon_list.htm">multiproxy.org</ulink> and many
+ more through Google. A particularly interesting project is the JAP service
+ offered by the Technical University of Dresden (<ulink
+ url="http://anon.inf.tu-dresden.de/index_en.html">http://anon.inf.tu-dresden.de/index_en.html</ulink>.
+</para>
+<para>
+ There is, however, even in the single-machine case the possibility to make the
+ server believe that your machine is in fact a shared proxy serving a whole big
+ LAN, and we are looking into that.
+</para>
+</sect2>
+
+<sect2 renderas="sect3">
+<title id="anonforsure">Can <application>Privoxy</application> guarantee I am anonymous?</title>
+<para>
+ No. Your chances of remaining anonymous are greatly improved, but unless you
+ are an expert on Internet security it would be safest to assume that
+ everything you do on the Web can be traced back to you.
+</para>
+<para>
+ <application>Privoxy</application> can remove various information about you,
+ and allows <emphasis>you</emphasis> more freedom to decide which sites
+ you can trust, and what details you want to reveal. But it's still possible
+ that web sites can find out who you are. Here's one way this can happen.
+</para>
+<para>
+ A few browsers disclose the user's email address in certain situations, such
+ as when transferring a file by FTP. <application>Privoxy</application>
+ does not filter FTP. If you need this feature, or are concerned about the
+ mail handler of your browser disclosing your email address, you might
+ consider products such as <application>NSClean</application>.
+</para>
+<para>
+ Browsers available only as binaries could use non-standard headers to give
+ out any information they can have access to: see the manufacturer's license
+ agreement. It's impossible to anticipate and prevent every breach of privacy
+ that might occur. The professionally paranoid prefer browsers available as
+ source code, because anticipating their behavior is easier. Trust the source,
+ Luke!
+</para>
+
+</sect2>
+
+<sect2 renderas="sect3">
+<title id="sitebreak">Might some things break because header information or
+content is being altered?</title>
+
+<para>
+ Definitely. More and more sites use HTTP header content to decide what to
+ display and how to display it. There is many ways that this can be handled,
+ so having hard and fast rules, is tricky.
+</para>
+
+<para>
+ <quote>User-Agent</quote> in particular 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 this.
+</para>
+
+<para>
+ For instance, different browsers use different encodings of Russian and Czech
+ characters, certain web servers convert pages on-the-fly according to the
+ User Agent header. Giving a <quote>User Agent</quote> with the wrong
+ operating system or browser manufacturer causes some sites in these languages
+ to be garbled; Surfers to Eastern European sites should change it to
+ something closer. And then some page access counters work by looking at the
+ <quote>Referer</quote> header; they may fail or break if unavailable. The
+ weather maps of Intellicast have been blocked by their server when no
+ <quote>Referer</quote> or cookie is provided, is another example. (But you
+ can forge both headers without giving information away). There are
+ many other ways things can go wrong when trying to fool a web server.
+</para>
+
+<para>
+ Similar thoughts apply to modifying JavaScript, and, to a lesser degree,
+ HTML elements.
+</para>
+
+<para>
+ If you have problems with a site, you will have to adjust your configuration
+ accordingly. Cookies are probably the most likely adjustment that may
+ be required, but by no means the only one.
+</para>
+
+</sect2>
+
+
+<sect2 renderas="sect3">
+<title id="caching">Can <application>Privoxy</application> act as a <quote>caching</quote> proxy to
+speed up web browsing?</title>
+<para>
+ No, it does not have this ability at all. You want something like
+ <ulink url="http://www.squid-cache.org/">Squid</ulink> for this. And, yes,
+ before you ask, <application>Privoxy</application> can co-exist
+ with other kinds of proxies like <application>Squid</application>.
+ See the <ulink url="../user-manual/config.html#FORWARDING">forwarding
+ chapter</ulink> in the <ulink url="../user-manual/index.html">user
+ manual</ulink> for details.
+</para>
+</sect2>
+
+<sect2 renderas="sect3">
+<title id="firewall">What about as a firewall? Can <application>Privoxy</application> protect me?</title>
+<para>
+ Not in the way you mean, or in the way a true firewall can.
+ <application>Privoxy</application> can help protect your privacy, but not
+ protect you from intrusion attempts. It is, of course, perfectly possible
+ and recommended to use <emphasis>both</emphasis>.
+</para>
+</sect2>
+
+<!-- No longer needed
+<sect2 renderas="sect3">
+<title id="logo">The <application>Privoxy</application> logo that replaces ads is very blocky
+and ugly looking. Can't a better font be used?</title>
+
+<para>
+ This is not a font problem. The logo is an image that is created by
+ <application>Privoxy</application> on the fly. So as to not waste
+ memory, the image is rather small. The blockiness comes when the
+ image is scaled to fill a largish area. There is not much to be done
+ about this, other than to use one of the other
+ <quote>imageblock</quote> directives: <emphasis>pattern</emphasis>,
+ <emphasis>blank</emphasis>, or a URL of your choosing.
+</para>
+<para>
+Given the above problem, we have decided to remove the logo option entirely
+[as of v2.9.13].
+</para>
+</sect2>
+-->
+
+<sect2 renderas="sect3">
+<title id="wasted">I have large empty spaces / a checkerboard pattern now where
+ads used to be. Why?</title>
+<para>
+ It would be technically possible eliminate the banners in a way that frees
+ their screen estate in many cases, by doing all banner blocking with filters,
+ i.e. eliminating the whole image references from the HTML pages instead
+ of letting them stay in, and blocking the resulting requests for the
+ banners themselves.
+</para>
+<para>
+ But this would consume considerable CPU resources, would likely destroy
+ the layout of many web pages which rely on the banners consuming a certain
+ amount of screen space, and would fail in other cases, where the screen space
+ is reserved e.g. by tables anyway. Also, making the banners disappear without
+ a visual trace complicates troubleshooting.
+</para>
+<para>
+ So we won't support this in the default configuration, but you can of course
+ define appropriate filters yourself.
+</para>
+</sect2>
+
+<sect2 renderas="sect3">
+<title id="ssl">How can <application>Privoxy</application> filter Secure (HTTPS) URLs?</title>
+<para>
+ Since secure HTTP connections are encrypted SSL sessions between your browser
+ and the secure site, and are meant to be reliably <emphasis>secure</emphasis>,
+ there is little that <application>Privoxy</application> can do but hand the raw
+ gibberish data though from one end to the other unprocessed.
+</para>
+<para>
+ The only exception to this is blocking by host patterns, as the client needs
+ to tell <application>Privoxy</application> the name of the remote server,
+ so that <application>Privoxy</application> can establish the connection.
+ If that name matches a host-only pattern, the connection will be blocked.
+</para>
+<para>
+ As far as ad blocking is concerned, this is less of a restriction than it may
+ seem, since ad sources are often identifiable by the host name, and often
+ the banners to be placed in an encrypted page come unencrypted nonetheless
+ for efficiency reasons, which exposes them to the full power of
+ <application>Privoxy</application>'s ad blocking.
+</para>
+
+</sect2>
+
+<sect2 renderas="sect3">
+<title id="secure"><application>Privoxy</application> runs as a <quote>server</quote>. How
+secure is it? Do I need to take any special precautions?</title>
+<para>
+ There are no known exploits that might affect
+ <application>Privoxy</application>. On Unix-like systems,
+ <application>Privoxy</application> can run as a non-privileged
+ user, which is how we recommend it be run. Also, by default
+ <application>Privoxy</application> only listens to requests
+ from <quote>localhost</quote> only. The server aspect of
+ <application>Privoxy</application> is not itself directly exposed to the
+ Internet in this configuration. If you want to have
+ <application>Privoxy</application> serve as a LAN proxy, this will have to
+ be opened up to allow for LAN requests. In this case, we'd recommend
+ you specify only the LAN gateway address, e.g. 192.168.1.1, in the main
+ <application>Privoxy</application> configuration file and check all <ulink
+ url="../user-manual/config.html#ACCESS-CONTROL">access control and security
+ options</ulink>. All LAN hosts can then use this as their proxy address
+ in the browser proxy configuration, but <application>Privoxy</application>
+ will not listen on any external interfaces. ACLs can be defined in addition,
+ and using a firewall is always good too. Better safe than sorry.
+</para>
+
+</sect2>
+
+<sect2 renderas="sect3" id="turnoff">
+<title>How can I temporarily disable <application>Privoxy</application>?</title>
+<para>
+ The easiest way is to access <application>Privoxy</application> with your
+ browser by using the remote toggle URL: <ulink
+ url="http://config.privoxy.org/toggle">http://config.privoxy.org/toggle</ulink>.
+</para>
+</sect2>
+
+<sect2 renderas="sect3" id="seealso">
+<title>Where can I find more information about <application>Privoxy</application>
+and related issues?</title>
+<!-- Include seealso.sgml boilerplate: -->
+ &seealso;
+<!-- end boilerplate -->
+
+<!--