+<!-- ~~~~~ New section ~~~~~ -->
+<sect3 renderas="sect4" id="fast-redirects">
+<title><emphasis>fast-redirects</emphasis></title>
+
+<variablelist>
+ <varlistentry>
+ <term>Typical use:</term>
+ <listitem>
+ <para>Fool some click-tracking scripts and speed up indirect links</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Effect:</term>
+ <listitem>
+ <para>
+ Cut off all but the last valid URL from requests.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Type:</term>
+ <!-- boolean, parameterized, Multi-value -->
+ <listitem>
+ <para>Boolean.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Parameter:</term>
+ <listitem>
+ <para>
+ N/A
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ Many sites, like yahoo.com, don't just link to other sites. Instead, they
+ will link to some script on their own servers, giving the destination as a
+ parameter, which will then redirect you to the final target. URLs
+ resulting from this scheme typically look like:
+ <emphasis>http://some.place/click-tracker.cgi?target=http://some.where.else</emphasis>.
+ </para>
+ <para>
+ Sometimes, there are even multiple consecutive redirects encoded in the
+ URL. These redirections via scripts make your web browsing more traceable,
+ since the server from which you follow such a link can see where you go
+ to. Apart from that, valuable bandwidth and time is wasted, while your
+ browser ask the server for one redirect after the other. Plus, it feeds
+ the advertisers.
+ </para>
+ <para>
+ This feature is currently not very smart and is scheduled for improvement.
+ It is likely to break some sites. There is a bunch of exceptions to this action in
+ <filename>default.action</filename>, should you decide to turn it on by default.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Example usage:</term>
+ <listitem>
+ <para>
+ <screen>{+fast-redirects}</screen>
+ </para>
+ </listitem>
+ </varlistentry>
+
+</variablelist>
+</sect3>
+
+
+<!-- ~~~~~ New section ~~~~~ -->
+<sect3 renderas="sect4" id="filter">
+<title><emphasis>filter</emphasis></title>
+
+<variablelist>
+ <varlistentry>
+ <term>Typical use:</term>
+ <listitem>
+ <para>Get rid of HTML and JavaScript annoyances, banner advertisements (by size), do fun text replacements, etc.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Effect:</term>
+ <listitem>
+ <para>
+ Text documents, including HTML and JavaScript, to which this action applies, are filterd on-the-fly
+ through the specified regular expression based substitutions.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Type:</term>
+ <!-- boolean, parameterized, Multi-value -->
+ <listitem>
+ <para>Parameterized.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Parameter:</term>
+ <listitem>
+ <para>
+ The name of a filter, as defined in the <link linkend="filter-file">filter file</link>
+ (typically <filename>default.filter</filename>, set by the
+ <literal><link linkend="filterfile">filterfile</link></literal>
+ option in the <link linkend="config">config file</link>)
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ For your convenience, there are a bunch of pre-defined filters available
+ in the distribution filter file that you can use. See the example below for
+ a list.
+ </para>
+ <para>
+ This is potentially a very powerful feature! But <quote>rolling your own</quote>
+ filters requires a knowledge of regular expressions and HTML.
+ </para>
+ <para>
+ Filtering requires buffering the page content, which may appear to
+ slow down page rendering since nothing is displayed until all content has
+ passed the filters. (It does not really take longer, but seems that way
+ since the page is not incrementally displayed.) This effect will be more
+ noticeable on slower connections.
+ </para>
+ <para>
+ At this time, <application>Privoxy</application> cannot (yet!) uncompress compressed
+ documents. If you want filtering to work on all documents, even those that
+ would normally be sent compressed, use the
+ <literal><link linkend="prevent-compression">prevent-compression</link></literal>
+ action in conjuction with <literal>filter</literal>.
+ </para>
+ <para>
+ Filtering can achieve some of the effects as the
+ <literal><link linkend="block">block</link></literal>
+ action, i.e. it can be used to block ads and banners.
+ </para>
+ <para>
+ <link linkend="contact">Feedback</link> with suggestions for new or improved filters is particularly
+ welcome!
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Example usage (with filters from the distribution <filename>default.filter</filename> file):</term>
+ <listitem>
+ <para>
+ <anchor id="filter-html-annoyances">
+ <screen>+filter{html-annoyances} # Get rid of particularly annoying HTML abuse.</screen>
+ </para>
+ <para>
+ <anchor id="filter-js-annoyances">
+ <screen>+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse</screen>
+ </para>
+ <para>
+ <anchor id="filter-banners-by-size">
+ <screen>+filter{banners-by-size} # Kill banners by size (<emphasis>very</emphasis> efficient!)</screen>
+ </para>
+ <para>
+ <anchor id="filter-content-cookies">
+ <screen>+filter{content-cookies} # Kill cookies that come sneaking in the HTML or JS content</screen>
+ </para>
+ <para>
+ <anchor id="filter-popups">
+ <screen>+filter{popups} # Kill all popups in JS and HTML</screen>
+ </para>
+ <para>
+ <anchor id="filter-webbugs">
+ <screen>+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking)</screen>
+ </para>
+ <para>
+ <anchor id="filter-fun">
+ <screen>+filter{fun} # Text replacements for subversive browsing fun!</screen>
+ </para>
+ <para>
+ <anchor id="filter-frameset-borders">
+ <screen>+filter{frameset-borders} # Give frames a border and make them resizable</screen>
+ </para>
+ <para>
+ <anchor id="filter-refresh-tags">
+ <screen>+filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups)</screen>
+ </para>
+ <para>
+ <anchor id="filter-nimda">
+ <screen>+filter{nimda} # Remove Nimda (virus) code.</screen>
+ </para>
+ <para>
+ <anchor id="filter-shockwave-flash">
+ <screen>+filter{shockwave-flash} # Kill embedded Shockwave Flash objects</screen>
+ </para>
+ <para>
+ <anchor id="filter-crude-parental">
+ <screen>+filter{crude-parental} # Kill all web pages that contain the words "sex" or "warez"</screen>
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</sect3>
+
+
+<!-- ~~~~~ New section ~~~~~ -->
+<sect3 renderas="sect4" id="handle-as-image">
+<title><emphasis>handle-as-image</emphasis></title>
+
+<variablelist>
+ <varlistentry>
+ <term>Typical use:</term>
+ <listitem>
+ <para>Mark URLs as belonging to images (so they'll be replaced by images <emphasis>if they get blocked</emphasis>)</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Effect:</term>
+ <listitem>
+ <para>
+ This action alone doesn't do anything noticeable. It just marks URLs as images.
+ If the <literal><link linkend="block">block</link></literal> action <emphasis>also applies</emphasis>,
+ the presence or absence of this mark decides whether an HTML <quote>blocked</quote>
+ page, or a replacement image (as determined by the <literal><link
+ linkend="set-image-blocker">set-image-blocker</link></literal> action) will be sent to the
+ client as a substitute for the blocked content.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Type:</term>
+ <!-- Boolean, Parameterized, Multi-value -->
+ <listitem>
+ <para>Boolean.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Parameter:</term>
+ <listitem>
+ <para>
+ N/A
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ The below generic example section is actually part of <filename>default.action</filename>.
+ It marks all URLs with well-known image file name extensions as images and should
+ be left intact.
+ </para>
+ <para>
+ Users will probably only want to use the handle-as-image action in conjunction with
+ <literal><link linkend="block">block</link></literal>, to block sources of banners, whose URLs don't
+ reflect the file type, like in the second example section.
+ </para>
+ <para>
+ Note that you cannot treat HTML pages as images in most cases. For instance, (inline) ad
+ frames require an HTML page to be sent, or they won't display properly.
+ Forcing <literal>handle-as-image</literal> in this situation will not replace the
+ ad frame with an image, but lead to error messages.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Example usage (sections):</term>
+ <listitem>
+ <para>
+ <screen># Generic image extensions:
+#
+{+handle-as-image}
+/.*\.(gif|jpg|jpeg|png|bmp|ico)$
+
+# These don't look like images, but they're banners and should be
+# blocked as images:
+#
+{+block +handle-as-image}
+some.nasty-banner-server.com/junk.cgi?output=trash
+
+# Banner source! Who cares if they also have non-image content?
+ad.doubleclick.net
+</screen>
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</sect3>
+
+
+<!-- ~~~~~ New section ~~~~~ -->
+<sect3 renderas="sect4" id="hide-forwarded-for-headers">
+<title><emphasis>hide-forwarded-for-headers</emphasis></title>
+
+<variablelist>
+ <varlistentry>
+ <term>Typical use:</term>
+ <listitem>
+ <para>Improve privacy by hiding the true source of the request</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Effect:</term>
+ <listitem>
+ <para>
+ Deletes any existing <quote>X-Forwarded-for:</quote> HTTP header from client requests,
+ and prevents adding a new one.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Type:</term>
+ <!-- Boolean, Parameterized, Multi-value -->
+ <listitem>
+ <para>Boolean.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Parameter:</term>
+ <listitem>
+ <para>
+ N/A
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ It is fairly safe to leave this on.
+ </para>
+ <para>
+ This action is scheduled for improvement: It should be able to generate forged
+ <quote>X-Forwarded-for:</quote> headers using random IP addresses from a specified network,
+ to make successive requests from the same client look like requests from a pool of different
+ users sharing the same proxy.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Example usage:</term>
+ <listitem>
+ <para>
+ <screen>+hide-forwarded-for-headers</screen>
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</sect3>
+
+
+<!-- ~~~~~ New section ~~~~~ -->
+<sect3 renderas="sect4" id="hide-from-header">
+<title><emphasis>hide-from-header</emphasis></title>
+
+<variablelist>
+ <varlistentry>
+ <term>Typical use:</term>
+ <listitem>
+ <para>Keep your (old and ill) browser from telling web servers your email address</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Effect:</term>
+ <listitem>
+ <para>
+ Deletes any existing <quote>From:</quote> HTTP header, or replaces it with the
+ specified string.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Type:</term>
+ <!-- Boolean, Parameterized, Multi-value -->
+ <listitem>
+ <para>Parameterized.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Parameter:</term>
+ <listitem>
+ <para>
+ Keyword: <quote>block</quote>, or any user defined value.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Notes:</term>
+ <listitem>
+ <para>
+ The keyword <quote>block</quote> will completely remove the header
+ (not to be confused with the <literal><link linkend="block">block</link></literal>
+ action).
+ </para>
+ <para>
+ Alternately, you can specify any value you prefer to be sent to the web
+ server. If you do, it is a matter of fairness not to use any address that
+ is actually used by a real person.
+ </para>
+ <para>
+ This action is rarely needed, as modern web browsers don't send
+ <quote>From:</quote> headers anymore.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term>Example usage:</term>
+ <listitem>
+ <para>
+ <screen>+hide-from-header{block}</screen> or
+ <screen>+hide-from-header{spam-me-senseless@sittingduck.example.com}</screen>
+ </para>
+ </listitem>
+ </varlistentry>
+</variablelist>
+</sect3>