1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd">
8 CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
10 TITLE="Privoxy 3.0.8 User Manual"
11 HREF="index.html"><LINK
13 TITLE="The Main Configuration File"
14 HREF="config.html"><LINK
17 HREF="filter-file.html"><LINK
20 HREF="../p_doc.css"><META
21 HTTP-EQUIV="Content-Type"
24 <LINK REL="STYLESHEET" TYPE="text/css" HREF="p_doc.css">
36 SUMMARY="Header navigation table"
45 >Privoxy 3.0.8 User Manual</TH
67 HREF="filter-file.html"
85 > The actions files are used to define what <SPAN
95 > takes for which URLs, and thus determines
96 how ad images, cookies and various other aspects of HTTP content and
97 transactions are handled, and on which sites (or even parts thereof).
98 There are a number of such actions, with a wide range of functionality.
99 Each action does something a little different.
100 These actions give us a veritable arsenal of tools with which to exert
101 our control, preferences and independence. Actions can be combined so that
102 their effects are aggregated when applied against a given set of URLs.</P
105 are three action files included with <SPAN
120 > - is the primary action file
121 that sets the initial values for all actions. It is intended to
122 provide a base level of functionality for
126 > array of features. So it is
127 a set of broad rules that should work reasonably well as-is for most users.
128 This is the file that the developers are keeping updated, and <A
129 HREF="installation.html#INSTALLATION-KEEPUPDATED"
130 >making available to users</A
132 The user's preferences as set in <TT
155 > - is intended to be for local site
156 preferences and exceptions. As an example, if your ISP or your bank
157 has specific requirements, and need special handling, this kind of
158 thing should go here. This file will not be upgraded.
166 > - is used only by the web based editor
168 HREF="http://config.privoxy.org/edit-actions-list?f=default"
170 > http://config.privoxy.org/edit-actions-list?f=default</A
172 to set various pre-defined sets of rules for the default actions section
184 >Set to Cautious</SPAN
190 >Set to Advanced</SPAN
194 > These have increasing levels of aggressiveness <SPAN
199 influence on your browsing unless you select them explicitly in the
202 >. A default installation should be pre-set to
206 > (versions prior to 3.0.5 were set to
210 >). New users should try this for a while before
211 adjusting the settings to more aggressive levels. The more aggressive
212 the settings, then the more likelihood there is of problems such as sites
213 not working as they should.
219 > button allows you to turn each
220 action on/off individually for fine-tuning. The <SPAN
224 button changes the actions list to low/safe settings which will activate
225 ad blocking and a minimal set of <SPAN
228 >'s features, and subsequently
229 there will be less of a chance for accidental problems. The
233 > button sets the list to a medium level of
234 other features and a low level set of privacy features. The
238 > button sets the list to a high level of
239 ad blocking and medium level of privacy. See the chart below. The latter
240 three buttons over-ride any changes via with the
244 > button. More fine-tuning can be done in the
245 lower sections of this internal page.
248 > It is not recommend to edit the <TT
255 > The default profiles, and their associated actions, as pre-defined in
269 >Table 1. Default Configurations</B
299 >Ad-blocking Aggressiveness</TD
309 >Ad-filtering by size</TD
319 >Ad-filtering by link</TD
339 >Privacy Features</TD
369 >GIF de-animation</TD
399 >JavaScript taming</TD
419 >Image tag reordering</TD
437 > The list of actions files to be used are defined in the main configuration
438 file, and are processed in the order they are defined (e.g.
442 > is typically processed before
446 >). The content of these can all be viewed and
448 HREF="http://config.privoxy.org/show-status"
450 >http://config.privoxy.org/show-status</A
452 The over-riding principle when applying actions, is that the last action that
453 matches a given URL wins. The broadest, most general rules go first
458 followed by any exceptions (typically also in
462 >), which are then followed lastly by any
463 local preferences (typically in <SPAN
479 > An actions file typically has multiple sections. If you want to use
483 > in an actions file, you have to place the (optional)
485 HREF="actions-file.html#ALIASES"
487 > at the top of that file.
488 Then comes the default set of rules which will apply universally to all
489 sites and pages (be <SPAN
499 > or any other actions file after
503 >, because it will override the result
504 from consulting any previous file). And then below that,
505 exceptions to the defined universal policies. You can regard
509 > as an appendix to <TT
513 with the advantage that it is a separate file, which makes preserving your
514 personal settings across <SPAN
517 > upgrades easier.</P
520 Actions can be used to block anything you want, including ads, banners, or
521 just some obnoxious URL whose content you would rather not see. Cookies can be accepted
522 or rejected, or accepted only during the current browser session (i.e. not
523 written to disk), content can be modified, some JavaScripts tamed, user-tracking
524 fooled, and much more. See below for a <A
525 HREF="actions-file.html#ACTIONS"
535 >8.1. Finding the Right Mix</A
539 HREF="actions-file.html#ACTIONS"
541 >, like cookie suppression
542 or script disabling, may render some sites unusable that rely on these
543 techniques to work properly. Finding the right mix of actions is not always easy and
544 certainly a matter of personal taste. And, things can always change, requiring
545 refinements in the configuration. In general, it can be said that the more
549 > your default settings (in the top section of the
550 actions file) are, the more exceptions for <SPAN
554 will have to make later. If, for example, you want to crunch all cookies per
555 default, you'll have to make exceptions from that rule for sites that you
556 regularly use and that require cookies for actually useful purposes, like maybe
557 your bank, favorite shop, or newspaper.</P
559 > We have tried to provide you with reasonable rules to start from in the
560 distribution actions files. But there is no general rule of thumb on these
561 things. There just are too many variables, and sites are constantly changing.
562 Sooner or later you will want to change the rules (and read this chapter again :).</P
573 > The easiest way to edit the actions files is with a browser by
574 using our browser-based editor, which can be reached from <A
575 HREF="http://config.privoxy.org/show-status"
577 >http://config.privoxy.org/show-status</A
579 Note: the config file option <A
580 HREF="config.html#ENABLE-EDIT-ACTIONS"
581 >enable-edit-actions</A
582 > must be enabled for
583 this to work. The editor allows both fine-grained control over every single
584 feature on a per-URL basis, and easy choosing from wholesale sets of defaults
595 >. Warning: the <SPAN
599 aggressive, and will be more likely to cause problems for some sites.
600 Experienced users only!
603 > If you prefer plain text editing to GUIs, you can of course also directly edit the
604 the actions files with your favorite text editor. Look at
608 > which is richly commented with many
617 >8.3. How Actions are Applied to Requests</A
620 > Actions files are divided into sections. There are special sections,
624 HREF="actions-file.html#ALIASES"
627 > sections which will
628 be discussed later. For now let's concentrate on regular sections: They have a
629 heading line (often split up to multiple lines for readability) which consist
630 of a list of actions, separated by whitespace and enclosed in curly braces.
631 Below that, there is a list of URL and tag patterns, each on a separate line.</P
633 > To determine which actions apply to a request, the URL of the request is
634 compared to all URL patterns in each <SPAN
638 Every time it matches, the list of applicable actions for the request is
639 incrementally updated, using the heading of the section in which the
640 pattern is located. The same is done again for tags and tag patterns later on.</P
642 > If multiple applying sections set the same action differently,
643 the last match wins. If not, the effects are aggregated.
644 E.g. a URL might match a regular section with a heading line of <TT
648 HREF="actions-file.html#HANDLE-AS-IMAGE"
652 then later another one with just <TT
656 HREF="actions-file.html#BLOCK"
666 > actions to apply. And there may well be
667 cases where you will want to combine actions together. Such a section then
685 # Block these as if they were images. Send no block page.
687 media.example.com/.*banners
688 .example.com/images/ads/</PRE
695 > You can trace this process for URL patterns and any given URL by visiting <A
696 HREF="http://config.privoxy.org/show-url-info"
698 >http://config.privoxy.org/show-url-info</A
701 > Examples and more detail on this is provided in the Appendix, <A
702 HREF="appendix.html#ACTIONSANAT"
703 > Troubleshooting: Anatomy of an Action</A
723 to determine what <SPAN
729 > might apply to which sites and
730 pages your browser attempts to access. These <SPAN
740 > matching to achieve a high degree of
741 flexibility. This allows one expression to be expanded and potentially match
742 against many similar patterns.</P
744 > Generally, an URL pattern has the form
747 ><domain>/<path></TT
751 ><domain></TT
756 optional. (This is why the special <TT
759 > pattern matches all
760 URLs). Note that the protocol portion of the URL pattern (e.g.
771 the pattern. This is assumed already!</P
773 > The pattern matching syntax is different for the domain and path parts of
774 the URL. The domain part uses a simple globbing type matching technique,
775 while the path part uses a more flexible
777 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
782 Expressions (PCRE)"</SPAN
793 >www.example.com/</TT
797 > is a domain-only pattern and will match any request to <TT
801 regardless of which document on that server is requested. So ALL pages in
802 this domain would be covered by the scope of this action. Note that a
806 > is different and would NOT match.
816 > means exactly the same. For domain-only patterns, the trailing <TT
826 >www.example.com/index.html$</TT
830 > matches all the documents on <TT
834 whose name starts with <TT
843 >www.example.com/index.html$</TT
847 > matches only the single document <TT
864 > matches the document <TT
867 >, regardless of the domain,
874 > web server anywhere.
884 > matches nothing, since it would be interpreted as a domain name and
885 there is no top-level domain called <TT
900 >8.4.1. The Domain Pattern</A
903 > The matching of the domain part offers some flexible options: if the
904 domain starts or ends with a dot, it becomes unanchored at that end.
918 > matches any domain with first-level domain <TT
922 and second-level domain <TT
935 >foo.bar.baz.example.com</TT
937 Note that it wouldn't match if the second-level domain was <TT
950 > matches any domain that <SPAN
960 > (It also matches the domain
964 > but most of the time that doesn't matter.)
974 > matches any domain that <SPAN
984 And, by the way, also included would be any files or documents that exist
985 within that domain since no path limitations are specified. (Correctly
986 speaking: It matches any FQDN that contains <TT
990 a domain.) This might be <TT
1000 >www.example.net/cgi/testing.pl</TT
1001 > for instance. All these
1008 > Additionally, there are wild-cards that you can use in the domain names
1009 themselves. These work similarly to shell globbing type wild-cards:
1013 > represents zero or more arbitrary characters (this is
1016 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
1023 > based syntax of <SPAN
1030 > represents any single character (this is equivalent to the
1031 regular expression syntax of a simple <SPAN
1034 >), and you can define
1037 >"character classes"</SPAN
1038 > in square brackets which is similar to
1039 the same regular expression technique. All of this can be freely mixed:</P
1043 CLASS="VARIABLELIST"
1048 >ad*.example.com</TT
1054 >"adserver.example.com"</SPAN
1058 >"ads.example.com"</SPAN
1059 >, etc but not <SPAN
1061 >"sfads.example.com"</SPAN
1068 >*ad*.example.com</TT
1072 > matches all of the above, and then some.
1088 >pictures.epix.com</TT
1091 >a.b.c.d.e.upix.com</TT
1098 >www[1-9a-ez].example.c*</TT
1104 >www1.example.com</TT
1108 >www4.example.cc</TT
1111 >wwwd.example.cy</TT
1115 >wwwz.example.com</TT
1125 >wwww.example.com</TT
1132 > While flexible, this is not the sophistication of full regular expression based syntax.</P
1140 >8.4.2. The Path Pattern</A
1146 > uses Perl compatible (PCRE)
1148 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
1157 HREF="http://www.pcre.org/"
1161 matching the path portion (after the slash), and is thus more flexible.</P
1164 HREF="appendix.html#REGEX"
1166 > with a brief quick-start into regular
1167 expressions, and full (very technical) documentation on PCRE regex syntax is available on-line
1169 HREF="http://www.pcre.org/man.txt"
1171 >http://www.pcre.org/man.txt</A
1173 You might also find the Perl man page on regular expressions (<TT
1177 useful, which is available on-line at <A
1178 HREF="http://perldoc.perl.org/perlre.html"
1180 >http://perldoc.perl.org/perlre.html</A
1183 > Note that the path pattern is automatically left-anchored at the <SPAN
1187 i.e. it matches as if it would start with a <SPAN
1190 > (regular expression speak
1191 for the beginning of a line).</P
1193 > Please also note that matching in the path is <SPAN
1197 >CASE INSENSITIVE</I
1200 by default, but you can switch to case sensitive at any point in the pattern by using the
1206 >www.example.com/(?-i)PaTtErN.*</TT
1208 only documents whose path starts with <TT
1218 > this capitalization.</P
1222 CLASS="VARIABLELIST"
1227 >.example.com/.*</TT
1231 > Is equivalent to just <SPAN
1233 >".example.com"</SPAN
1234 >, since any documents
1235 within that domain are matched with or without the <SPAN
1239 regular expression. This is redundant
1245 >.example.com/.*/index.html$</TT
1249 > Will match any page in the domain of <SPAN
1251 >"example.com"</SPAN
1256 >, and that is part of some path. For
1257 example, it matches <SPAN
1259 >"www.example.com/testing/index.html"</SPAN
1263 >"www.example.com/index.html"</SPAN
1264 > because the regular
1265 expression called for at least two <SPAN
1269 requirement. It also would match
1272 >"www.example.com/testing/index_html"</SPAN
1274 special meta-character <SPAN
1283 >.example.com/(.*/)?index\.html$</TT
1287 > This regular expression is conditional so it will match any page
1291 > regardless of path which in this case can
1292 have one or more <SPAN
1295 >. And this one must contain exactly
1299 > (but does not have to end with that!).
1305 >.example.com/(.*/)(ads|banners?|junk)</TT
1309 > This regular expression will match any path of <SPAN
1311 >"example.com"</SPAN
1313 that contains any of the words <SPAN
1323 > (because of the <SPAN
1330 The path does not have to end in these words, just contain them.
1336 >.example.com/(.*/)(ads|banners?|junk)/.*\.(jpe?g|gif|png)$</TT
1340 > This is very much the same as above, except now it must end in either
1354 one is limited to common image formats.
1360 > There are many, many good examples to be found in <TT
1364 and more tutorials below in <A
1365 HREF="appendix.html#REGEX"
1366 >Appendix on regular expressions</A
1375 >8.4.3. The Tag Pattern</A
1378 > Tag patterns are used to change the applying actions based on the
1379 request's tags. Tags can be created with either the
1381 HREF="actions-file.html#CLIENT-HEADER-TAGGER"
1382 >client-header-tagger</A
1385 HREF="actions-file.html#SERVER-HEADER-TAGGER"
1386 >server-header-tagger</A
1389 > Tag patterns have to start with <SPAN
1396 can tell them apart from URL patterns. Everything after the colon
1397 including white space, is interpreted as a regular expression with
1398 path pattern syntax, except that tag patterns aren't left-anchored
1399 automatically (<SPAN
1402 > doesn't silently add a <SPAN
1406 you have to do it yourself if you need it).</P
1408 > To match all requests that are tagged with <SPAN
1412 your pattern line should be <SPAN
1419 > would work as well, but it would also
1420 match requests whose tags contain <SPAN
1427 > wouldn't work as it requires white space.</P
1429 > Sections can contain URL and tag patterns at the same time,
1430 but tag patterns are checked after the URL patterns and thus
1431 always overrule them, even if they are located before the URL patterns.</P
1433 > Once a new tag is added, Privoxy checks right away if it's matched by one
1434 of the tag patterns and updates the action settings accordingly. As a result
1435 tags can be used to activate other tagger actions, as long as these other
1436 taggers look for headers that haven't already be parsed.</P
1438 > For example you could tag client requests which use the
1443 then use this tag to activate another tagger that adds a tag if cookies
1444 are sent, and then use a block action based on the cookie tag. This allows
1445 the outcome of one action, to be input into a subsequent action. However if
1446 you'd reverse the position of the described taggers, and activated the
1447 method tagger based on the cookie tagger, no method tags would be created.
1448 The method tagger would look for the request line, but at the time
1449 the cookie tag is created, the request line has already been parsed.</P
1451 > While this is a limitation you should be aware of, this kind of
1452 indirection is seldom needed anyway and even the example doesn't
1453 make too much sense.</P
1465 > All actions are disabled by default, until they are explicitly enabled
1466 somewhere in an actions file. Actions are turned on if preceded with a
1470 >, and turned off if preceded with a <SPAN
1479 >"do that action"</SPAN
1486 >"please block URLs that match the
1487 following patterns"</SPAN
1494 block URLs that match the following patterns, even if <TT
1498 previously applied."</SPAN
1502 Again, actions are invoked by placing them on a line, enclosed in curly braces and
1503 separated by whitespace, like in
1506 >{+some-action -some-other-action{some-parameter}}</TT
1508 followed by a list of URL patterns, one per line, to which they apply.
1509 Together, the actions line and the following pattern lines make up a section
1510 of the actions file. </P
1513 Actions fall into three categories:</P
1521 Boolean, i.e the action can only be <SPAN
1544 > # enable action <TT
1555 > # disable action <TT
1577 Parameterized, where some value is required in order to enable this type of action.
1599 >} # enable action and set parameter to <TT
1605 # overwriting parameter from previous match if necessary
1611 > # disable action. The parameter can be omitted</PRE
1618 > Note that if the URL matches multiple positive forms of a parameterized action,
1619 the last match wins, i.e. the params from earlier matches are simply ignored.
1625 >+hide-user-agent{Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.8.1.4) Gecko/20070602 Firefox/2.0.0.4}</TT
1632 Multi-value. These look exactly like parameterized actions,
1633 but they behave differently: If the action applies multiple times to the
1634 same URL, but with different parameters, <SPAN
1647 > matches are remembered. This is used for actions
1648 that can be executed for the same request repeatedly, like adding multiple
1649 headers, or filtering through multiple filters. Syntax:
1670 >} # enable action and add <TT
1675 > to the list of parameters
1686 >} # remove the parameter <TT
1691 > from the list of parameters
1692 # If it was the last one left, disable the action.
1698 > # disable this action completely and remove all parameters from the list</PRE
1708 >+add-header{X-Fun-Header: Some text}</TT
1712 >+filter{html-annoyances}</TT
1719 > If nothing is specified in any actions file, no <SPAN
1723 taken. So in this case <SPAN
1727 normal, non-blocking, non-filtering proxy. You must specifically enable the
1728 privacy and blocking features you need (although the provided default actions
1729 files will give a good starting point).</P
1731 > Later defined action sections always over-ride earlier ones of the same type.
1732 So exceptions to any rules you make, should come in the latter part of the file (or
1733 in a file that is processed later when using multiple actions files such
1737 >). For multi-valued actions, the actions
1738 are applied in the order they are specified. Actions files are processed in
1739 the order they are defined in <TT
1743 installation has three actions files). It also quite possible for any given
1744 URL to match more than one <SPAN
1747 > (because of wildcards and
1748 regular expressions), and thus to trigger more than one set of actions! Last
1751 > The list of valid <SPAN
1761 >8.5.1. add-header</A
1766 CLASS="VARIABLELIST"
1772 >Confuse log analysis, custom applications</P
1778 > Sends a user defined HTTP header to the web server.
1791 > Any string value is possible. Validity of the defined HTTP headers is not checked.
1792 It is recommended that you use the <SPAN
1806 > This action may be specified multiple times, in order to define multiple
1807 headers. This is rarely needed for the typical user. If you don't know what
1810 >"HTTP headers"</SPAN
1811 > are, you definitely don't need to worry about this
1827 >+add-header{X-User-Tracking: sucks}</PRE
1848 CLASS="VARIABLELIST"
1854 >Block ads or other unwanted content</P
1860 > Requests for URLs to which this action applies are blocked, i.e. the
1861 requests are trapped by <SPAN
1864 > and the requested URL is never retrieved,
1865 but is answered locally with a substitute page or image, as determined by
1869 HREF="actions-file.html#HANDLE-AS-IMAGE"
1876 HREF="actions-file.html#SET-IMAGE-BLOCKER"
1877 >set-image-blocker</A
1883 HREF="actions-file.html#HANDLE-AS-EMPTY-DOCUMENT"
1884 >handle-as-empty-document</A
1909 > sends a special <SPAN
1913 for requests to blocked pages. This page contains links to find out why the request
1914 was blocked, and a click-through to the blocked content (the latter only if compiled with the
1915 force feature enabled). The <SPAN
1918 > page adapts to the available
1919 screen space -- it displays full-blown if space allows, or miniaturized and text-only
1920 if loaded into a small frame or window. If you are using <SPAN
1924 right now, you can take a look at the
1926 HREF="http://ads.bannerserver.example.com/nasty-ads/sponsor.html"
1937 A very important exception occurs if <SPAN
1950 HREF="actions-file.html#HANDLE-AS-IMAGE"
1954 apply to the same request: it will then be replaced by an image. If
1958 HREF="actions-file.html#SET-IMAGE-BLOCKER"
1959 >set-image-blocker</A
1962 (see below) also applies, the type of image will be determined by its parameter,
1963 if not, the standard checkerboard pattern is sent.
1966 > It is important to understand this process, in order
1967 to understand how <SPAN
1971 ads and other unwanted content. Blocking is a core feature, and one
1972 upon which various other features depend.
1978 HREF="actions-file.html#FILTER"
1982 action can perform a very similar task, by <SPAN
1986 banner images and other content through rewriting the relevant URLs in the
1987 document's HTML source, so they don't get requested in the first place.
1988 Note that this is a totally different technique, and it's easy to confuse the two.
1992 >Example usage (section):</DT
2004 # Block and replace with "blocked" page
2005 .nasty-stuff.example.com
2007 {+block +handle-as-image}
2008 # Block and replace with image
2012 {+block +handle-as-empty-document}
2013 # Block and then ignore
2014 adserver.exampleclick.net/.*\.js$</PRE
2029 NAME="CLIENT-HEADER-FILTER"
2030 >8.5.3. client-header-filter</A
2035 CLASS="VARIABLELIST"
2041 > Rewrite or remove single client headers.
2048 > All client headers to which this action applies are filtered on-the-fly through
2049 the specified regular expression based substitutions.
2062 > The name of a client-header filter, as defined in one of the
2064 HREF="filter-file.html"
2073 > Client-header filters are applied to each header on its own, not to
2074 all at once. This makes it easier to diagnose problems, but on the downside
2075 you can't write filters that only change header x if header y's value is z.
2076 You can do that by using tags though.
2079 > Client-header filters are executed after the other header actions have finished
2080 and use their output as input.
2083 > If the request URL gets changed, <SPAN
2086 > will detect that and use the new
2087 one. This can be used to rewrite the request destination behind the client's
2088 back, for example to specify a Tor exit relay for certain requests.
2091 > Please refer to the <A
2092 HREF="filter-file.html"
2093 >filter file chapter</A
2095 to learn which client-header filters are available by default, and how to
2100 >Example usage (section):</DT
2111 >{+client-header-filter{hide-tor-exit-notation}}
2128 NAME="CLIENT-HEADER-TAGGER"
2129 >8.5.4. client-header-tagger</A
2134 CLASS="VARIABLELIST"
2140 > Block requests based on their headers.
2147 > Client headers to which this action applies are filtered on-the-fly through
2148 the specified regular expression based substitutions, the result is used as
2162 > The name of a client-header tagger, as defined in one of the
2164 HREF="filter-file.html"
2173 > Client-header taggers are applied to each header on its own,
2174 and as the header isn't modified, each tagger <SPAN
2181 > Client-header taggers are the first actions that are executed
2182 and their tags can be used to control every other action.
2186 >Example usage (section):</DT
2197 ># Tag every request with the User-Agent header
2198 {+client-header-tagger{user-agent}}
2215 NAME="CONTENT-TYPE-OVERWRITE"
2216 >8.5.5. content-type-overwrite</A
2221 CLASS="VARIABLELIST"
2227 >Stop useless download menus from popping up, or change the browser's rendering mode</P
2233 > Replaces the <SPAN
2235 >"Content-Type:"</SPAN
2236 > HTTP server header.
2258 >"Content-Type:"</SPAN
2259 > HTTP server header is used by the
2260 browser to decide what to do with the document. The value of this
2261 header can cause the browser to open a download menu instead of
2262 displaying the document by itself, even if the document's format is
2263 supported by the browser.
2266 > The declared content type can also affect which rendering mode
2267 the browser chooses. If XHTML is delivered as <SPAN
2271 many browsers treat it as yet another broken HTML document.
2272 If it is send as <SPAN
2274 >"application/xml"</SPAN
2276 XHTML support will only display it, if the syntax is correct.
2279 > If you see a web site that proudly uses XHTML buttons, but sets
2282 >"Content-Type: text/html"</SPAN
2283 >, you can use <SPAN
2287 to overwrite it with <SPAN
2289 >"application/xml"</SPAN
2291 the web master's claim inside your XHTML-supporting browser.
2292 If the syntax is incorrect, the browser will complain loudly.
2295 > You can also go the opposite direction: if your browser prints
2296 error messages instead of rendering a document falsely declared
2297 as XHTML, you can overwrite the content type with
2301 > and have it rendered as broken HTML document.
2306 >content-type-overwrite</TT
2310 >"Content-Type:"</SPAN
2311 > headers that look like some kind of text.
2312 If you want to overwrite it unconditionally, you have to combine it with
2316 HREF="actions-file.html#FORCE-TEXT-MODE"
2320 This limitation exists for a reason, think twice before circumventing it.
2323 > Most of the time it's easier to replace this action with a custom
2327 HREF="actions-file.html#SERVER-HEADER-FILTER"
2328 >server-header filter</A
2331 It allows you to activate it for every document of a certain site and it will still
2332 only replace the content types you aimed at.
2335 > Of course you can apply <TT
2337 >content-type-overwrite</TT
2339 to a whole site and then make URL based exceptions, but it's a lot
2340 more work to get the same precision.
2344 >Example usage (sections):</DT
2355 ># Check if www.example.net/ really uses valid XHTML
2356 { +content-type-overwrite{application/xml} }
2359 # but leave the content type unmodified if the URL looks like a style sheet
2360 {-content-type-overwrite}
2361 www.example.net/.*\.css$
2362 www.example.net/.*style</PRE
2377 NAME="CRUNCH-CLIENT-HEADER"
2378 >8.5.6. crunch-client-header</A
2383 CLASS="VARIABLELIST"
2389 >Remove a client header <SPAN
2392 > has no dedicated action for.</P
2398 > Deletes every header sent by the client that contains the string the user supplied as parameter.
2418 > This action allows you to block client headers for which no dedicated
2426 > will remove every client header that
2427 contains the string you supplied as parameter.
2430 > Regular expressions are <SPAN
2437 use this action to block different headers in the same request, unless
2438 they contain the same string.
2443 >crunch-client-header</TT
2444 > is only meant for quick tests.
2445 If you have to block several different headers, or only want to modify
2446 parts of them, you should use a
2450 HREF="actions-file.html#CLIENT-HEADER-FILTER"
2451 >client-header filter</A
2474 > Don't block any header without understanding the consequences.
2482 >Example usage (section):</DT
2493 ># Block the non-existent "Privacy-Violation:" client header
2494 { +crunch-client-header{Privacy-Violation:} }
2511 NAME="CRUNCH-IF-NONE-MATCH"
2512 >8.5.7. crunch-if-none-match</A
2517 CLASS="VARIABLELIST"
2523 >Prevent yet another way to track the user's steps between sessions.</P
2531 >"If-None-Match:"</SPAN
2532 > HTTP client header.
2552 > Removing the <SPAN
2554 >"If-None-Match:"</SPAN
2555 > HTTP client header
2556 is useful for filter testing, where you want to force a real
2557 reload instead of getting status code <SPAN
2561 would cause the browser to use a cached copy of the page.
2564 > It is also useful to make sure the header isn't used as a cookie
2565 replacement (unlikely but possible).
2568 > Blocking the <SPAN
2570 >"If-None-Match:"</SPAN
2571 > header shouldn't cause any
2572 caching problems, as long as the <SPAN
2574 >"If-Modified-Since:"</SPAN
2576 isn't blocked or missing as well.
2579 > It is recommended to use this action together with
2583 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
2584 >hide-if-modified-since</A
2591 HREF="actions-file.html#OVERWRITE-LAST-MODIFIED"
2592 >overwrite-last-modified</A
2598 >Example usage (section):</DT
2609 ># Let the browser revalidate cached documents but don't
2610 # allow the server to use the revalidation headers for user tracking.
2611 {+hide-if-modified-since{-60} \
2612 +overwrite-last-modified{randomize} \
2613 +crunch-if-none-match}
2629 NAME="CRUNCH-INCOMING-COOKIES"
2630 >8.5.8. crunch-incoming-cookies</A
2635 CLASS="VARIABLELIST"
2641 > Prevent the web server from setting HTTP cookies on your system
2650 >"Set-Cookie:"</SPAN
2651 > HTTP headers from server replies.
2671 > This action is only concerned with <SPAN
2688 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
2689 >crunch-outgoing-cookies</A
2698 > to disable HTTP cookies completely.
2707 > to use this action in conjunction
2711 HREF="actions-file.html#SESSION-COOKIES-ONLY"
2712 >session-cookies-only</A
2715 since it would prevent the session cookies from being set. See also
2719 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
2720 >filter-content-cookies</A
2737 >+crunch-incoming-cookies</PRE
2752 NAME="CRUNCH-SERVER-HEADER"
2753 >8.5.9. crunch-server-header</A
2758 CLASS="VARIABLELIST"
2764 >Remove a server header <SPAN
2767 > has no dedicated action for.</P
2773 > Deletes every header sent by the server that contains the string the user supplied as parameter.
2793 > This action allows you to block server headers for which no dedicated
2797 > action exists. <SPAN
2801 will remove every server header that contains the string you supplied as parameter.
2804 > Regular expressions are <SPAN
2811 use this action to block different headers in the same request, unless
2812 they contain the same string.
2817 >crunch-server-header</TT
2818 > is only meant for quick tests.
2819 If you have to block several different headers, or only want to modify
2820 parts of them, you should use a custom
2824 HREF="actions-file.html#SERVER-HEADER-FILTER"
2825 >server-header filter</A
2848 > Don't block any header without understanding the consequences.
2856 >Example usage (section):</DT
2867 ># Crunch server headers that try to prevent caching
2868 { +crunch-server-header{no-cache} }
2884 NAME="CRUNCH-OUTGOING-COOKIES"
2885 >8.5.10. crunch-outgoing-cookies</A
2890 CLASS="VARIABLELIST"
2896 > Prevent the web server from reading any HTTP cookies from your system
2906 > HTTP headers from client requests.
2926 > This action is only concerned with <SPAN
2943 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
2944 >crunch-incoming-cookies</A
2953 > to disable HTTP cookies completely.
2962 > to use this action in conjunction
2966 HREF="actions-file.html#SESSION-COOKIES-ONLY"
2967 >session-cookies-only</A
2970 since it would prevent the session cookies from being read.
2985 >+crunch-outgoing-cookies</PRE
3000 NAME="DEANIMATE-GIFS"
3001 >8.5.11. deanimate-gifs</A
3006 CLASS="VARIABLELIST"
3012 >Stop those annoying, distracting animated GIF images.</P
3018 > De-animate GIF animations, i.e. reduce them to their first or last image.
3044 > This will also shrink the images considerably (in bytes, not pixels!). If
3048 > is given, the first frame of the animation
3049 is used as the replacement. If <SPAN
3052 > is given, the last
3053 frame of the animation is used instead, which probably makes more sense for
3054 most banner animations, but also has the risk of not showing the entire
3055 last frame (if it is only a delta to an earlier frame).
3058 > You can safely use this action with patterns that will also match non-GIF
3059 objects, because no attempt will be made at anything that doesn't look like
3075 >+deanimate-gifs{last}</PRE
3090 NAME="DOWNGRADE-HTTP-VERSION"
3091 >8.5.12. downgrade-http-version</A
3096 CLASS="VARIABLELIST"
3102 >Work around (very rare) problems with HTTP/1.1</P
3108 > Downgrades HTTP/1.1 client requests and server replies to HTTP/1.0.
3128 > This is a left-over from the time when <SPAN
3132 didn't support important HTTP/1.1 features well. It is left here for the
3133 unlikely case that you experience HTTP/1.1 related problems with some server
3134 out there. Not all HTTP/1.1 features and requirements are supported yet,
3135 so there is a chance you might need this action.
3139 >Example usage (section):</DT
3150 >{+downgrade-http-version}
3151 problem-host.example.com</PRE
3166 NAME="FAST-REDIRECTS"
3167 >8.5.13. fast-redirects</A
3172 CLASS="VARIABLELIST"
3178 >Fool some click-tracking scripts and speed up indirect links.</P
3184 > Detects redirection URLs and redirects the browser without contacting
3185 the redirection server first.
3204 >"simple-check"</SPAN
3205 > to just search for the string <SPAN
3209 to detect redirection URLs.
3216 >"check-decoded-url"</SPAN
3217 > to decode URLs (if necessary) before searching
3218 for redirection URLs.
3228 Many sites, like yahoo.com, don't just link to other sites. Instead, they
3229 will link to some script on their own servers, giving the destination as a
3230 parameter, which will then redirect you to the final target. URLs
3231 resulting from this scheme typically look like:
3234 >"http://www.example.org/click-tracker.cgi?target=http%3a//www.example.net/"</SPAN
3238 > Sometimes, there are even multiple consecutive redirects encoded in the
3239 URL. These redirections via scripts make your web browsing more traceable,
3240 since the server from which you follow such a link can see where you go
3241 to. Apart from that, valuable bandwidth and time is wasted, while your
3242 browser asks the server for one redirect after the other. Plus, it feeds
3246 > This feature is currently not very smart and is scheduled for improvement.
3247 If it is enabled by default, you will have to create some exceptions to
3248 this action. It can lead to failures in several ways:
3251 > Not every URLs with other URLs as parameters is evil.
3252 Some sites offer a real service that requires this information to work.
3253 For example a validation service needs to know, which document to validate.
3257 > assumes that every URL parameter that
3258 looks like another URL is a redirection target, and will always redirect to
3259 the last one. Most of the time the assumption is correct, but if it isn't,
3260 the user gets redirected anyway.
3263 > Another failure occurs if the URL contains other parameters after the URL parameter.
3267 >"http://www.example.org/?redirect=http%3a//www.example.net/&foo=bar"</SPAN
3269 contains the redirection URL <SPAN
3271 >"http://www.example.net/"</SPAN
3273 followed by another parameter. <TT
3277 and will cause a redirect to <SPAN
3279 >"http://www.example.net/&foo=bar"</SPAN
3281 Depending on the target server configuration, the parameter will be silently ignored
3284 >"page not found"</SPAN
3285 > error. You can prevent this problem by
3289 HREF="actions-file.html#REDIRECT"
3293 to remove the last part of the URL, but it requires a little effort.
3296 > To detect a redirection URL, <TT
3300 looks for the string <SPAN
3303 >, either in plain text
3304 (invalid but often used) or encoded as <SPAN
3308 Some sites use their own URL encoding scheme, encrypt the address
3309 of the target server or replace it with a database id. In theses cases
3313 > is fooled and the request reaches the
3314 redirection server where it probably gets logged.
3329 > { +fast-redirects{simple-check} }
3332 { +fast-redirects{check-decoded-url} }
3333 another.example.com/testing</PRE
3354 CLASS="VARIABLELIST"
3360 >Get rid of HTML and JavaScript annoyances, banner advertisements (by size),
3361 do fun text replacements, add personalized effects, etc.</P
3367 > All instances of text-based type, most notably HTML and JavaScript, to which
3368 this action applies, can be filtered on-the-fly through the specified regular
3369 expression based substitutions. (Note: as of version 3.0.3 plain text documents
3370 are exempted from filtering, because web servers often use the
3374 > MIME type for all files whose type they don't know.)
3387 > The name of a content filter, as defined in the <A
3388 HREF="filter-file.html"
3391 Filters can be defined in one or more files as defined by the
3395 HREF="config.html#FILTERFILE"
3406 > is the collection of filters
3407 supplied by the developers. Locally defined filters should go
3408 in their own file, such as <TT
3414 > When used in its negative form,
3415 and without parameters, <SPAN
3421 > filtering is completely disabled.
3428 > For your convenience, there are a number of pre-defined filters available
3429 in the distribution filter file that you can use. See the examples below for
3433 > Filtering requires buffering the page content, which may appear to
3434 slow down page rendering since nothing is displayed until all content has
3435 passed the filters. (It does not really take longer, but seems that way
3436 since the page is not incrementally displayed.) This effect will be more
3437 noticeable on slower connections.
3442 >"Rolling your own"</SPAN
3444 filters requires a knowledge of
3446 HREF="http://en.wikipedia.org/wiki/Regular_expressions"
3455 HREF="http://en.wikipedia.org/wiki/Html"
3462 This is very powerful feature, and potentially very intrusive.
3463 Filters should be used with caution, and where an equivalent
3470 > The amount of data that can be filtered is limited to the
3474 HREF="config.html#BUFFER-LIMIT"
3478 option in the main <A
3482 default is 4096 KB (4 Megs). Once this limit is exceeded, the buffered
3483 data, and all pending data, is passed through unfiltered.
3486 > Inappropriate MIME types, such as zipped files, are not filtered at all.
3487 (Again, only text-based types except plain text). Encrypted SSL data
3488 (from HTTPS servers) cannot be filtered either, since this would violate
3489 the integrity of the secure transaction. In some situations it might
3490 be necessary to protect certain text, like source code, from filtering
3491 by defining appropriate <TT
3497 > Compressed content can't be filtered either, unless <SPAN
3501 is compiled with zlib support (requires at least <SPAN
3508 > will decompress the content before filtering
3512 > If you use a <SPAN
3515 > version without zlib support, but want filtering to work on
3516 as much documents as possible, even those that would normally be sent compressed,
3517 you must use the <TT
3520 HREF="actions-file.html#PREVENT-COMPRESSION"
3521 >prevent-compression</A
3524 action in conjunction with <TT
3530 > Content filtering can achieve some of the same effects as the
3534 HREF="actions-file.html#BLOCK"
3538 action, i.e. it can be used to block ads and banners. But the mechanism
3539 works quite differently. One effective use, is to block ad banners
3540 based on their size (see below), since many of these seem to be somewhat
3547 > with suggestions for new or
3548 improved filters is particularly welcome!
3551 > The below list has only the names and a one-line description of each
3552 predefined filter. There are <A
3553 HREF="filter-file.html#PREDEFINED-FILTERS"
3555 verbose explanations</A
3556 > of what these filters do in the <A
3557 HREF="filter-file.html"
3558 >filter file chapter</A
3563 >Example usage (with filters from the distribution <TT
3568 HREF="filter-file.html#PREDEFINED-FILTERS"
3569 >the Predefined Filters section</A
3571 more explanation on each:</DT
3575 NAME="FILTER-JS-ANNOYANCES"
3586 >+filter{js-annoyances} # Get rid of particularly annoying JavaScript abuse</PRE
3594 NAME="FILTER-JS-EVENTS"
3605 >+filter{js-events} # Kill all JS event bindings (Radically destructive! Only for extra nasty sites)</PRE
3613 NAME="FILTER-HTML-ANNOYANCES"
3624 >+filter{html-annoyances} # Get rid of particularly annoying HTML abuse</PRE
3632 NAME="FILTER-CONTENT-COOKIES"
3643 >+filter{content-cookies} # Kill cookies that come in the HTML or JS content</PRE
3651 NAME="FILTER-REFRESH-TAGS"
3662 >+filter{refresh-tags} # Kill automatic refresh tags (for dial-on-demand setups)</PRE
3670 NAME="FILTER-UNSOLICITED-POPUPS"
3681 >+filter{unsolicited-popups} # Disable only unsolicited pop-up windows. Useful if your browser lacks this ability.</PRE
3689 NAME="FILTER-ALL-POPUPS"
3700 >+filter{all-popups} # Kill all popups in JavaScript and HTML. Useful if your browser lacks this ability.</PRE
3708 NAME="FILTER-IMG-REORDER"
3719 >+filter{img-reorder} # Reorder attributes in <img> tags to make the banners-by-* filters more effective</PRE
3727 NAME="FILTER-BANNERS-BY-SIZE"
3738 >+filter{banners-by-size} # Kill banners by size</PRE
3746 NAME="FILTER-BANNERS-BY-LINK"
3757 >+filter{banners-by-link} # Kill banners by their links to known clicktrackers</PRE
3765 NAME="FILTER-WEBBUGS"
3776 >+filter{webbugs} # Squish WebBugs (1x1 invisible GIFs used for user tracking)</PRE
3784 NAME="FILTER-TINY-TEXTFORMS"
3795 >+filter{tiny-textforms} # Extend those tiny textareas up to 40x80 and kill the hard wrap</PRE
3803 NAME="FILTER-JUMPING-WINDOWS"
3814 >+filter{jumping-windows} # Prevent windows from resizing and moving themselves</PRE
3822 NAME="FILTER-FRAMESET-BORDERS"
3833 >+filter{frameset-borders} # Give frames a border and make them resizeable</PRE
3841 NAME="FILTER-DEMORONIZER"
3852 >+filter{demoronizer} # Fix MS's non-standard use of standard charsets</PRE
3860 NAME="FILTER-SHOCKWAVE-FLASH"
3871 >+filter{shockwave-flash} # Kill embedded Shockwave Flash objects</PRE
3879 NAME="FILTER-QUICKTIME-KIOSKMODE"
3890 >+filter{quicktime-kioskmode} # Make Quicktime movies savable</PRE
3909 >+filter{fun} # Text replacements for subversive browsing fun!</PRE
3917 NAME="FILTER-CRUDE-PARENTAL"
3928 >+filter{crude-parental} # Crude parental filtering (demo only)</PRE
3936 NAME="FILTER-IE-EXPLOITS"
3947 >+filter{ie-exploits} # Disable a known Internet Explorer bug exploits</PRE
3955 NAME="FILTER-SITE-SPECIFICS"
3966 >+filter{site-specifics} # Custom filters for specific site related problems</PRE
3974 NAME="FILTER-GOOGLE"
3985 >+filter{google} # Removes text ads and other Google specific improvements</PRE
4004 >+filter{yahoo} # Removes text ads and other Yahoo specific improvements</PRE
4023 >+filter{msn} # Removes text ads and other MSN specific improvements</PRE
4031 NAME="FILTER-BLOGSPOT"
4042 >+filter{blogspot} # Cleans up Blogspot blogs</PRE
4050 NAME="FILTER-NO-PING"
4061 >+filter{no-ping} # Removes non-standard ping attributes from anchor and area tags</PRE
4076 NAME="FORCE-TEXT-MODE"
4077 >8.5.15. force-text-mode</A
4082 CLASS="VARIABLELIST"
4091 > to treat a document as if it was in some kind of <SPAN
4103 > Declares a document as text, even if the <SPAN
4105 >"Content-Type:"</SPAN
4106 > isn't detected as such.
4129 HREF="actions-file.html#FILTER"
4136 > tries to only filter files that are
4137 in some kind of text format. The same restrictions apply to
4141 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
4142 >content-type-overwrite</A
4147 >force-text-mode</TT
4148 > declares a document as text,
4149 without looking at the <SPAN
4151 >"Content-Type:"</SPAN
4173 > Think twice before activating this action. Filtering binary data
4174 with regular expressions can cause file damage.
4209 NAME="FORWARD-OVERRIDE"
4210 >8.5.16. forward-override</A
4215 CLASS="VARIABLELIST"
4221 >Change the forwarding settings based on User-Agent or request origin</P
4227 > Overrules the forward directives in the configuration file.
4247 > to use a direct connection without any additional proxies.</P
4253 >"forward 127.0.0.1:8123"</SPAN
4254 > to use the HTTP proxy listening at 127.0.0.1 port 8123.
4261 >"forward-socks4a 127.0.0.1:9050 ."</SPAN
4262 > to use the socks4a proxy listening at
4263 127.0.0.1 port 9050. Replace <SPAN
4265 >"forward-socks4a"</SPAN
4268 >"forward-socks4"</SPAN
4270 to use a socks4 connection (with local DNS resolution) instead.
4277 >"forward-socks4a 127.0.0.1:9050 proxy.example.org:8000"</SPAN
4278 > to use the socks4a proxy
4279 listening at 127.0.0.1 port 9050 to reach the HTTP proxy listening at proxy.example.org port 8000.
4282 >"forward-socks4a"</SPAN
4285 >"forward-socks4"</SPAN
4286 > to use a socks4 connection
4287 (with local DNS resolution) instead.
4296 > This action takes parameters similar to the
4298 HREF="config.html#FORWARDING"
4300 > directives in the configuration
4301 file, but without the URL pattern. It can be used as replacement, but normally it's only
4302 used in cases where matching based on the request URL isn't sufficient.
4323 > Please read the description for the <A
4324 HREF="config.html#FORWARDING"
4327 using this action. Forwarding to the wrong people will reduce your privacy and increase the
4328 chances of man-in-the-middle attacks.
4331 > If the ports are missing or invalid, default values will be used. This might change
4332 in the future and you shouldn't rely on it. Otherwise incorrect syntax causes Privoxy
4337 HREF="http://config.privoxy.org/show-url-info"
4339 >show-url-info CGI page</A
4341 to verify that your forward settings do what you thought the do.
4360 ># Always use direct connections for requests previously tagged as
4363 >"User-Agent: fetch libfetch/2.0"</SPAN
4365 # resuming downloads continues to work.
4366 # This way you can continue to use Tor for your normal browsing,
4367 # without overloading the Tor network with your FreeBSD ports updates
4368 # or downloads of bigger files like ISOs.
4369 # Note that HTTP headers are easy to fake and therefore their
4370 # values are as (un)trustworthy as your clients and users.
4371 {+forward-override{forward .} \
4372 -hide-if-modified-since \
4373 -overwrite-last-modified \
4375 TAG:^User-Agent: fetch libfetch/2\.0$
4391 NAME="HANDLE-AS-EMPTY-DOCUMENT"
4392 >8.5.17. handle-as-empty-document</A
4397 CLASS="VARIABLELIST"
4403 >Mark URLs that should be replaced by empty documents <SPAN
4407 >if they get blocked</I
4415 > This action alone doesn't do anything noticeable. It just marks URLs.
4419 HREF="actions-file.html#BLOCK"
4429 the presence or absence of this mark decides whether an HTML <SPAN
4433 page, or an empty document will be sent to the client as a substitute for the blocked content.
4440 > document isn't literally empty, but actually contains a single space.
4460 > Some browsers complain about syntax errors if JavaScript documents
4461 are blocked with <SPAN
4465 default HTML page; this option can be used to silence them.
4466 And of course this action can also be used to eliminate the <SPAN
4470 BLOCKED message in frames.
4473 > The content type for the empty document can be specified with
4477 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
4478 >content-type-overwrite{}</A
4481 but usually this isn't necessary.
4496 ># Block all documents on example.org that end with ".js",
4497 # but send an empty document instead of the usual HTML message.
4498 {+block +handle-as-empty-document}
4515 NAME="HANDLE-AS-IMAGE"
4516 >8.5.18. handle-as-image</A
4521 CLASS="VARIABLELIST"
4527 >Mark URLs as belonging to images (so they'll be replaced by images <SPAN
4531 >if they do get blocked</I
4533 >, rather than HTML pages)</P
4539 > This action alone doesn't do anything noticeable. It just marks URLs as images.
4543 HREF="actions-file.html#BLOCK"
4553 the presence or absence of this mark decides whether an HTML <SPAN
4557 page, or a replacement image (as determined by the <TT
4560 HREF="actions-file.html#SET-IMAGE-BLOCKER"
4561 >set-image-blocker</A
4563 > action) will be sent to the
4564 client as a substitute for the blocked content.
4584 > The below generic example section is actually part of <TT
4588 It marks all URLs with well-known image file name extensions as images and should
4592 > Users will probably only want to use the handle-as-image action in conjunction with
4596 HREF="actions-file.html#BLOCK"
4599 >, to block sources of banners, whose URLs don't
4600 reflect the file type, like in the second example section.
4603 > Note that you cannot treat HTML pages as images in most cases. For instance, (in-line) ad
4604 frames require an HTML page to be sent, or they won't display properly.
4607 >handle-as-image</TT
4608 > in this situation will not replace the
4609 ad frame with an image, but lead to error messages.
4613 >Example usage (sections):</DT
4624 ># Generic image extensions:
4627 /.*\.(gif|jpg|jpeg|png|bmp|ico)$
4629 # These don't look like images, but they're banners and should be
4630 # blocked as images:
4632 {+block +handle-as-image}
4633 some.nasty-banner-server.com/junk.cgi\?output=trash
4635 # Banner source! Who cares if they also have non-image content?
4636 ad.doubleclick.net </PRE
4651 NAME="HIDE-ACCEPT-LANGUAGE"
4652 >8.5.19. hide-accept-language</A
4657 CLASS="VARIABLELIST"
4663 >Pretend to use different language settings.</P
4669 > Deletes or replaces the <SPAN
4671 >"Accept-Language:"</SPAN
4672 > HTTP header in client requests.
4688 >, or any user defined value.
4695 > Faking the browser's language settings can be useful to make a
4696 foreign User-Agent set with
4700 HREF="actions-file.html#HIDE-USER-AGENT"
4707 > However some sites with content in different languages check the
4710 >"Accept-Language:"</SPAN
4711 > to decide which one to take by default.
4712 Sometimes it isn't possible to later switch to another language without
4715 >"Accept-Language:"</SPAN
4719 > Therefore it's a good idea to either only change the
4722 >"Accept-Language:"</SPAN
4723 > header to languages you understand,
4724 or to languages that aren't wide spread.
4727 > Before setting the <SPAN
4729 >"Accept-Language:"</SPAN
4731 to a rare language, you should consider that it helps to
4732 make your requests unique and thus easier to trace.
4733 If you don't plan to change this header frequently,
4734 you should stick to a common language.
4738 >Example usage (section):</DT
4749 ># Pretend to use Canadian language settings.
4750 {+hide-accept-language{en-ca} \
4751 +hide-user-agent{Mozilla/5.0 (X11; U; OpenBSD i386; en-CA; rv:1.8.0.4) Gecko/20060628 Firefox/1.5.0.4} \
4768 NAME="HIDE-CONTENT-DISPOSITION"
4769 >8.5.20. hide-content-disposition</A
4774 CLASS="VARIABLELIST"
4780 >Prevent download menus for content you prefer to view inside the browser.</P
4786 > Deletes or replaces the <SPAN
4788 >"Content-Disposition:"</SPAN
4789 > HTTP header set by some servers.
4805 >, or any user defined value.
4812 > Some servers set the <SPAN
4814 >"Content-Disposition:"</SPAN
4816 documents they assume you want to save locally before viewing them.
4819 >"Content-Disposition:"</SPAN
4820 > header contains the file name
4821 the browser is supposed to use by default.
4824 > In most browsers that understand this header, it makes it impossible to
4831 > the document, without downloading it first,
4832 even if it's just a simple text file or an image.
4835 > Removing the <SPAN
4837 >"Content-Disposition:"</SPAN
4839 to prevent this annoyance, but some browsers additionally check the
4842 >"Content-Type:"</SPAN
4843 > header, before they decide if they can
4844 display a document without saving it first. In these cases, you have
4845 to change this header as well, before the browser stops displaying
4849 > It is also possible to change the server's file name suggestion
4850 to another one, but in most cases it isn't worth the time to set
4854 > This action will probably be removed in the future,
4855 use server-header filters instead.
4870 ># Disarm the download link in Sourceforge's patch tracker
4872 +content-type-overwrite{text/plain}\
4873 +hide-content-disposition{block} }
4874 .sourceforge.net/tracker/download\.php</PRE
4889 NAME="HIDE-IF-MODIFIED-SINCE"
4890 >8.5.21. hide-if-modified-since</A
4895 CLASS="VARIABLELIST"
4901 >Prevent yet another way to track the user's steps between sessions.</P
4909 >"If-Modified-Since:"</SPAN
4910 > HTTP client header or modifies its value.
4926 >, or a user defined value that specifies a range of hours.
4933 > Removing this header is useful for filter testing, where you want to force a real
4934 reload instead of getting status code <SPAN
4937 >, which would cause the
4938 browser to use a cached copy of the page.
4941 > Instead of removing the header, <TT
4943 >hide-if-modified-since</TT
4945 also add or subtract a random amount of time to/from the header's value.
4946 You specify a range of minutes where the random factor should be chosen from and
4950 > does the rest. A negative value means
4951 subtracting, a positive value adding.
4954 > Randomizing the value of the <SPAN
4956 >"If-Modified-Since:"</SPAN
4958 it less likely that the server can use the time as a cookie replacement,
4959 but you will run into caching problems if the random range is too high.
4962 > It is a good idea to only use a small negative value and let
4966 HREF="actions-file.html#OVERWRITE-LAST-MODIFIED"
4967 >overwrite-last-modified</A
4970 handle the greater changes.
4973 > It is also recommended to use this action together with
4977 HREF="actions-file.html#CRUNCH-IF-NONE-MATCH"
4978 >crunch-if-none-match</A
4981 otherwise it's more or less pointless.
4985 >Example usage (section):</DT
4996 ># Let the browser revalidate but make tracking based on the time less likely.
4997 {+hide-if-modified-since{-60} \
4998 +overwrite-last-modified{randomize} \
4999 +crunch-if-none-match}
5015 NAME="HIDE-FORWARDED-FOR-HEADERS"
5016 >8.5.22. hide-forwarded-for-headers</A
5021 CLASS="VARIABLELIST"
5027 >Improve privacy by not forwarding the source of the request in the HTTP headers.</P
5033 > Deletes any existing <SPAN
5035 >"X-Forwarded-for:"</SPAN
5036 > HTTP header from client requests.
5056 > It is safe and recommended to leave this on.
5071 >+hide-forwarded-for-headers</PRE
5086 NAME="HIDE-FROM-HEADER"
5087 >8.5.23. hide-from-header</A
5092 CLASS="VARIABLELIST"
5098 >Keep your (old and ill) browser from telling web servers your email address</P
5104 > Deletes any existing <SPAN
5107 > HTTP header, or replaces it with the
5124 >, or any user defined value.
5134 > will completely remove the header
5135 (not to be confused with the <TT
5138 HREF="actions-file.html#BLOCK"
5145 > Alternately, you can specify any value you prefer to be sent to the web
5146 server. If you do, it is a matter of fairness not to use any address that
5147 is actually used by a real person.
5150 > This action is rarely needed, as modern web browsers don't send
5169 >+hide-from-header{block}</PRE
5182 >+hide-from-header{spam-me-senseless@sittingduck.example.com}</PRE
5197 NAME="HIDE-REFERRER"
5198 >8.5.24. hide-referrer</A
5206 CLASS="VARIABLELIST"
5212 >Conceal which link you followed to get to a particular site</P
5221 > (sic) HTTP header from the client request,
5222 or replaces it with a forged one.
5241 >"conditional-block"</SPAN
5242 > to delete the header completely if the host has changed.</P
5248 >"conditional-forge"</SPAN
5249 > to forge the header if the host has changed.</P
5256 > to delete the header unconditionally.</P
5263 > to pretend to be coming from the homepage of the server we are talking to.</P
5267 >Any other string to set a user defined referrer.</P
5277 >conditional-block</TT
5278 > is the only parameter,
5279 that isn't easily detected in the server's log file. If it blocks the
5280 referrer, the request will look like the visitor used a bookmark or
5281 typed in the address directly.
5284 > Leaving the referrer unmodified for requests on the same host
5285 allows the server owner to see the visitor's <SPAN
5289 but in most cases she could also get that information by comparing
5290 other parts of the log file: for example the User-Agent if it isn't
5291 a very common one, or the user's IP address if it doesn't change between
5295 > Always blocking the referrer, or using a custom one, can lead to
5296 failures on servers that check the referrer before they answer any
5297 requests, in an attempt to prevent their content from being
5298 embedded or linked to elsewhere.
5303 >conditional-block</TT
5308 will work with referrer checks, as long as content and valid referring page
5309 are on the same host. Most of the time that's the case.
5316 > is an alternate spelling of
5320 > and the two can be can be freely
5321 substituted with each other. (<SPAN
5325 correct English spelling, however the HTTP specification has a bug - it
5326 requires it to be spelled as <SPAN
5344 >+hide-referrer{forge}</PRE
5357 >+hide-referrer{http://www.yahoo.com/}</PRE
5372 NAME="HIDE-USER-AGENT"
5373 >8.5.25. hide-user-agent</A
5378 CLASS="VARIABLELIST"
5384 >Try to conceal your type of browser and client operating system</P
5390 > Replaces the value of the <SPAN
5392 >"User-Agent:"</SPAN
5394 in client requests with the specified value.
5407 > Any user-defined string.
5432 > This can lead to problems on web sites that depend on looking at this header in
5433 order to customize their content for different browsers (which, by the
5440 > the right thing to do: good web sites
5441 work browser-independently).
5448 > Using this action in multi-user setups or wherever different types of
5449 browsers will access the same <SPAN
5459 >. In single-user, single-browser
5460 setups, you might use it to delete your OS version information from
5461 the headers, because it is an invitation to exploit known bugs for your
5462 OS. It is also occasionally useful to forge this in order to access
5463 sites that won't let you in otherwise (though there may be a good
5464 reason in some cases). Example of this: some MSN sites will not
5468 > enter, yet forging to a
5472 > user-agent works just fine.
5473 (Must be just a silly MS goof, I'm sure :-).
5476 > More information on known user-agent strings can be found at
5478 HREF="http://www.user-agents.org/"
5480 >http://www.user-agents.org/</A
5484 HREF="http://en.wikipedia.org/wiki/User_agent"
5486 >http://en.wikipedia.org/wiki/User_agent</A
5502 >+hide-user-agent{Netscape 6.1 (X11; I; Linux 2.4.18 i686)}</PRE
5517 NAME="INSPECT-JPEGS"
5518 >8.5.26. inspect-jpegs</A
5523 CLASS="VARIABLELIST"
5529 >Try to protect against a MS buffer over-run in JPEG processing</P
5535 > Protect against a known exploit
5555 > See Microsoft Security Bulletin MS04-028. JPEG images are one of the most
5556 common image types found across the Internet. The exploit as described can
5557 allow execution of code on the target system, giving an attacker access
5558 to the system in question by merely planting an altered JPEG image, which
5559 would have no obvious indications of what lurks inside. This action
5560 tries to prevent this exploit if delivered through unencrypted HTTP.
5563 > Note that the exploit mentioned is several years old
5564 and it's unlikely that your client is still vulnerable
5565 against it. This action may be removed in one of the
5581 >+inspect-jpegs</PRE
5596 >8.5.27. kill-popups<A
5604 CLASS="VARIABLELIST"
5610 >Eliminate those annoying pop-up windows (deprecated)</P
5616 > While loading the document, replace JavaScript code that opens
5617 pop-up windows with (syntactically neutral) dummy code on the fly.
5637 > This action is basically a built-in, hardwired special-purpose filter
5638 action, but there are important differences: For <TT
5642 the document need not be buffered, so it can be incrementally rendered while
5643 downloading. But <TT
5646 > doesn't catch as many pop-ups as
5650 HREF="actions-file.html#FILTER-ALL-POPUPS"
5659 does and is not as smart as <TT
5662 HREF="actions-file.html#FILTER-UNSOLICITED-POPUPS"
5666 >unsolicited-popups</I
5674 > Think of it as a fast and efficient replacement for a filter that you
5675 can use if you don't want any filtering at all. Note that it doesn't make
5676 sense to combine it with any <TT
5679 HREF="actions-file.html#FILTER"
5683 since as soon as one <TT
5686 HREF="actions-file.html#FILTER"
5690 the whole document needs to be buffered anyway, which destroys the advantage of
5694 > action over its filter equivalent.
5697 > Killing all pop-ups unconditionally is problematic. Many shops and banks rely on
5698 pop-ups to display forms, shopping carts etc, and the <TT
5701 HREF="actions-file.html#FILTER-UNSOLICITED-POPUPS"
5705 >unsolicited-popups</I
5710 > does a better job of catching only the unwanted ones.
5713 > If the only kind of pop-ups that you want to kill are exit consoles (those
5720 > windows that appear when you close an other
5721 one), you might want to use
5725 HREF="actions-file.html#FILTER"
5737 > This action is most appropriate for browsers that don't have any controls
5738 for unwanted pop-ups. Not recommended for general usage.
5741 > This action doesn't work very reliable and may be removed in future releases.
5770 NAME="LIMIT-CONNECT"
5771 >8.5.28. limit-connect</A
5776 CLASS="VARIABLELIST"
5782 >Prevent abuse of <SPAN
5785 > as a TCP proxy relay or disable SSL for untrusted sites</P
5791 > Specifies to which ports HTTP CONNECT requests are allowable.
5804 > A comma-separated list of ports or port ranges (the latter using dashes, with the minimum
5805 defaulting to 0 and the maximum to 65K).
5812 > By default, i.e. if no <TT
5819 > only allows HTTP CONNECT
5820 requests to port 443 (the standard, secure HTTPS port). Use
5824 > if more fine-grained control is desired
5825 for some or all destinations.
5828 > The CONNECT methods exists in HTTP to allow access to secure websites
5832 > URLs) through proxies. It works very simply:
5833 the proxy connects to the server on the specified port, and then
5834 short-circuits its connections to the client and to the remote server.
5835 This means CONNECT-enabled proxies can be used as TCP relays very easily.
5841 > relays HTTPS traffic without seeing
5842 the decoded content. Websites can leverage this limitation to circumvent <SPAN
5846 filters. By specifying an invalid port range you can disable HTTPS entirely.
5847 If you plan to disable SSL by default, consider enabling
5851 HREF="actions-file.html#TREAT-FORBIDDEN-CONNECTS-LIKE-BLOCKS"
5852 >treat-forbidden-connects-like-blocks</A
5855 as well, to be able to quickly create exceptions.
5859 >Example usages:</DT
5870 >+limit-connect{443} # This is the default and need not be specified.
5871 +limit-connect{80,443} # Ports 80 and 443 are OK.
5872 +limit-connect{-3, 7, 20-100, 500-} # Ports less than 3, 7, 20 to 100 and above 500 are OK.
5873 +limit-connect{-} # All ports are OK
5874 +limit-connect{,} # No HTTPS/SSL traffic is allowed</PRE
5889 NAME="PREVENT-COMPRESSION"
5890 >8.5.29. prevent-compression</A
5895 CLASS="VARIABLELIST"
5901 > Ensure that servers send the content uncompressed, so it can be
5905 HREF="actions-file.html#FILTER"
5915 > Removes the Accept-Encoding header which can be used to ask for compressed transfer.
5935 > More and more websites send their content compressed by default, which
5936 is generally a good idea and saves bandwidth. But the <TT
5939 HREF="actions-file.html#FILTER"
5945 HREF="actions-file.html#DEANIMATE-GIFS"
5952 HREF="actions-file.html#KILL-POPUPS"
5956 access to the uncompressed data.
5959 > When compiled with zlib support (available since <SPAN
5962 > 3.0.7), content that should be
5963 filtered is decompressed on-the-fly and you don't have to worry about this action.
5964 If you are using an older <SPAN
5967 > version, or one that hasn't been compiled with zlib
5968 support, this action can be used to convince the server to send the content uncompressed.
5971 > Most text-based instances compress very well, the size is seldom decreased by less than 50%,
5972 for markup-heavy instances like news feeds saving more than 90% of the original size isn't
5976 > Not using compression will therefore slow down the transfer, and you should only
5977 enable this action if you really need it. As of <SPAN
5980 > 3.0.7 it's disabled in all
5981 predefined action settings.
5984 > Note that some (rare) ill-configured sites don't handle requests for uncompressed
5985 documents correctly. Broken PHP applications tend to send an empty document body,
5986 some IIS versions only send the beginning of the content. If you enable
5989 >prevent-compression</TT
5990 > per default, you might want to add
5991 exceptions for those sites. See the example for how to do that.
5995 >Example usage (sections):</DT
6006 ># Selectively turn off compression, and enable a filter
6008 { +filter{tiny-textforms} +prevent-compression }
6009 # Match only these sites
6014 # Or instead, we could set a universal default:
6016 { +prevent-compression }
6019 # Then maybe make exceptions for broken sites:
6021 { -prevent-compression }
6037 NAME="OVERWRITE-LAST-MODIFIED"
6038 >8.5.30. overwrite-last-modified</A
6043 CLASS="VARIABLELIST"
6049 >Prevent yet another way to track the user's steps between sessions.</P
6057 >"Last-Modified:"</SPAN
6058 > HTTP server header or modifies its value.
6071 > One of the keywords: <SPAN
6076 >"reset-to-request-time"</SPAN
6088 > Removing the <SPAN
6090 >"Last-Modified:"</SPAN
6091 > header is useful for filter
6092 testing, where you want to force a real reload instead of getting status
6096 >, which would cause the browser to reuse the old
6097 version of the page.
6103 > option overwrites the value of the
6106 >"Last-Modified:"</SPAN
6107 > header with a randomly chosen time
6108 between the original value and the current time. In theory the server
6109 could send each document with a different <SPAN
6111 >"Last-Modified:"</SPAN
6113 header to track visits without using cookies. <SPAN
6117 makes it impossible and the browser can still revalidate cached documents.
6122 >"reset-to-request-time"</SPAN
6123 > overwrites the value of the
6126 >"Last-Modified:"</SPAN
6127 > header with the current time. You could use
6128 this option together with
6132 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
6133 >hided-if-modified-since</A
6136 to further customize your random range.
6139 > The preferred parameter here is <SPAN
6143 to use, as long as the time settings are more or less correct.
6144 If the server sets the <SPAN
6146 >"Last-Modified:"</SPAN
6147 > header to the time
6148 of the request, the random range becomes zero and the value stays the same.
6149 Therefore you should later randomize it a second time with
6153 HREF="actions-file.html#HIDE-IF-MODIFIED-SINCE"
6154 >hided-if-modified-since</A
6160 > It is also recommended to use this action together with
6164 HREF="actions-file.html#CRUNCH-IF-NONE-MATCH"
6165 >crunch-if-none-match</A
6182 ># Let the browser revalidate without being tracked across sessions
6183 { +hide-if-modified-since{-60} \
6184 +overwrite-last-modified{randomize} \
6185 +crunch-if-none-match}
6202 >8.5.31. redirect</A
6207 CLASS="VARIABLELIST"
6213 > Redirect requests to other sites.
6220 > Convinces the browser that the requested document has been moved
6221 to another location and the browser should get it from there.
6234 > An absolute URL or a single pcrs command.
6241 > Requests to which this action applies are answered with a
6242 HTTP redirect to URLs of your choosing. The new URL is
6243 either provided as parameter, or derived by applying a
6244 single pcrs command to the original URL.
6247 > This action will be ignored if you use it together with
6251 HREF="actions-file.html#BLOCK"
6255 It can be combined with
6259 HREF="actions-file.html#FAST-REDIRECTS"
6260 >fast-redirects{check-decoded-url}</A
6263 to redirect to a decoded version of a rewritten URL.
6266 > Use this action carefully, make sure not to create redirection loops
6267 and be aware that using your own redirects might make it
6268 possible to fingerprint your requests.
6272 >Example usages:</DT
6283 ># Replace example.com's style sheet with another one
6284 { +redirect{http://localhost/css-replacements/example.com.css} }
6285 example.com/stylesheet\.css
6287 # Create a short, easy to remember nickname for a favorite site
6288 # (relies on the browser accept and forward invalid URLs to <SPAN
6292 { +redirect{http://www.privoxy.org/user-manual/actions-file.html} }
6295 # Always use the expanded view for Undeadly.org articles
6296 # (Note the $ at the end of the URL pattern to make sure
6297 # the request for the rewritten URL isn't redirected as well)
6298 {+redirect{s@$@&mode=expanded@}}
6299 undeadly.org/cgi\?action=article&sid=\d*$</PRE
6314 NAME="SEND-VANILLA-WAFER"
6315 >8.5.32. send-vanilla-wafer</A
6320 CLASS="VARIABLELIST"
6326 > Feed log analysis scripts with useless data.
6333 > Sends a cookie with each request stating that you do not accept any copyright
6334 on cookies sent to you, and asking the site operator not to track you.
6354 > The vanilla wafer is a (relatively) unique header and could conceivably be used to track you.
6357 > This action is rarely used and not enabled in the default configuration.
6372 >+send-vanilla-wafer</PRE
6388 >8.5.33. send-wafer</A
6393 CLASS="VARIABLELIST"
6399 > Send custom cookies or feed log analysis scripts with even more useless data.
6406 > Sends a custom, user-defined cookie with each request.
6419 > A string of the form <SPAN
6439 > Being multi-valued, multiple instances of this action can apply to the same request,
6440 resulting in multiple cookies being sent.
6443 > This action is rarely used and not enabled in the default configuration.
6447 >Example usage (section):</DT
6458 >{+send-wafer{UsingPrivoxy=true}}
6459 my-internal-testing-server.void</PRE
6474 NAME="SERVER-HEADER-FILTER"
6475 >8.5.34. server-header-filter</A
6480 CLASS="VARIABLELIST"
6486 > Rewrite or remove single server headers.
6493 > All server headers to which this action applies are filtered on-the-fly
6494 through the specified regular expression based substitutions.
6507 > The name of a server-header filter, as defined in one of the
6509 HREF="filter-file.html"
6518 > Server-header filters are applied to each header on its own, not to
6519 all at once. This makes it easier to diagnose problems, but on the downside
6520 you can't write filters that only change header x if header y's value is z.
6521 You can do that by using tags though.
6524 > Server-header filters are executed after the other header actions have finished
6525 and use their output as input.
6528 > Please refer to the <A
6529 HREF="filter-file.html"
6530 >filter file chapter</A
6532 to learn which server-header filters are available by default, and how to
6537 >Example usage (section):</DT
6548 >{+server-header-filter{html-to-xml}}
6549 example.org/xml-instance-that-is-delivered-as-html
6551 {+server-header-filter{xml-to-html}}
6552 example.org/instance-that-is-delivered-as-xml-but-is-not
6568 NAME="SERVER-HEADER-TAGGER"
6569 >8.5.35. server-header-tagger</A
6574 CLASS="VARIABLELIST"
6580 > Enable or disable filters based on the Content-Type header.
6587 > Server headers to which this action applies are filtered on-the-fly through
6588 the specified regular expression based substitutions, the result is used as
6602 > The name of a server-header tagger, as defined in one of the
6604 HREF="filter-file.html"
6613 > Server-header taggers are applied to each header on its own,
6614 and as the header isn't modified, each tagger <SPAN
6621 > Server-header taggers are executed before all other header actions
6622 that modify server headers. Their tags can be used to control
6623 all of the other server-header actions, the content filters
6624 and the crunch actions (<A
6625 HREF="actions-file.html#REDIRECT"
6629 HREF="actions-file.html#BLOCK"
6634 > Obviously crunching based on tags created by server-header taggers
6635 doesn't prevent the request from showing up in the server's log file.
6639 >Example usage (section):</DT
6650 ># Tag every request with the content type declared by the server
6651 {+server-header-tagger{content-type}}
6668 NAME="SESSION-COOKIES-ONLY"
6669 >8.5.36. session-cookies-only</A
6674 CLASS="VARIABLELIST"
6680 > Allow only temporary <SPAN
6683 > cookies (for the current
6684 browser session <SPAN
6702 >"Set-Cookie:"</SPAN
6704 server headers. Most browsers will not store such cookies permanently and
6705 forget them in between sessions.
6725 > This is less strict than <TT
6728 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6729 >crunch-incoming-cookies</A
6735 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6736 >crunch-outgoing-cookies</A
6738 > and allows you to browse
6739 websites that insist or rely on setting cookies, without compromising your privacy too badly.
6742 > Most browsers will not permanently store cookies that have been processed by
6745 >session-cookies-only</TT
6746 > and will forget about them between sessions.
6747 This makes profiling cookies useless, but won't break sites which require cookies so
6748 that you can log in for transactions. This is generally turned on for all
6749 sites, and is the recommended setting.
6760 >session-cookies-only</TT
6765 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
6766 >crunch-incoming-cookies</A
6772 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
6773 >crunch-outgoing-cookies</A
6775 >. If you do, cookies
6776 will be plainly killed.
6779 > Note that it is up to the browser how it handles such cookies without an <SPAN
6783 field. If you use an exotic browser, you might want to try it out to be sure.
6786 > This setting also has no effect on cookies that may have been stored
6787 previously by the browser before starting <SPAN
6791 These would have to be removed manually.
6799 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
6800 >content-cookies filter</A
6802 to block some types of cookies. Content cookies are not effected by
6805 >session-cookies-only</TT
6821 >+session-cookies-only</PRE
6836 NAME="SET-IMAGE-BLOCKER"
6837 >8.5.37. set-image-blocker</A
6842 CLASS="VARIABLELIST"
6848 >Choose the replacement for blocked images</P
6854 > This action alone doesn't do anything noticeable. If <SPAN
6864 HREF="actions-file.html#BLOCK"
6876 HREF="actions-file.html#HANDLE-AS-IMAGE"
6886 apply, i.e. if the request is to be blocked as an image,
6893 > the parameter of this action decides what will be
6894 sent as a replacement.
6914 > to send a built-in checkerboard pattern image. The image is visually
6915 decent, scales very well, and makes it obvious where banners were busted.
6923 > to send a built-in transparent image. This makes banners disappear
6924 completely, but makes it hard to detect where <SPAN
6928 images on a given page and complicates troubleshooting if <SPAN
6932 has blocked innocent images, like navigation icons.
6946 send a redirect to <TT
6952 to any image anywhere, even in your local filesystem via <SPAN
6956 (But note that not all browsers support redirecting to a local file system).
6959 > A good application of redirects is to use special <SPAN
6963 URLs, which send the built-in images, as <TT
6969 This has the same visual effect as specifying <SPAN
6976 the first place, but enables your browser to cache the replacement image, instead of requesting
6977 it over and over again.
6986 > The URLs for the built-in images are <SPAN
6988 >"http://config.privoxy.org/send-banner?type=<TT
7009 > There is a third (advanced) type, called <SPAN
7021 >set-image-blocker</TT
7022 >, but meant for use from <A
7023 HREF="filter-file.html"
7026 Auto will select the type of image that would have applied to the referring page, had it been an image.
7044 >+set-image-blocker{pattern}</PRE
7051 > Redirect to the BSD daemon:
7062 >+set-image-blocker{http://www.freebsd.org/gifs/dae_up3.gif}</PRE
7069 > Redirect to the built-in pattern for better caching:
7080 >+set-image-blocker{http://config.privoxy.org/send-banner?type=pattern}</PRE
7095 NAME="TREAT-FORBIDDEN-CONNECTS-LIKE-BLOCKS"
7096 >8.5.38. treat-forbidden-connects-like-blocks</A
7101 CLASS="VARIABLELIST"
7107 >Block forbidden connects with an easy to find error message.</P
7113 > If this action is enabled, <SPAN
7117 makes a difference between forbidden connects and ordinary blocks.
7141 HREF="actions-file.html#LIMIT-CONNECT"
7147 with a short error message inside the headers. If the browser doesn't display
7148 headers (most don't), you just see an empty page.
7151 > With this action enabled, <SPAN
7155 the message that is used for ordinary blocks instead. If you decide
7156 to make an exception for the page in question, you can do so by
7166 > requests the clients tell
7170 > which host they are interested
7171 in, but not which document they plan to get later. As a result, the
7174 >"Go there anyway"</SPAN
7175 > wouldn't work and is therefore suppressed.
7190 >+treat-forbidden-connects-like-blocks</PRE
7209 > Note that many of these actions have the potential to cause a page to
7210 misbehave, possibly even not to display at all. There are many ways
7211 a site designer may choose to design his site, and what HTTP header
7212 content, and other criteria, he may depend on. There is no way to have hard
7213 and fast rules for all sites. See the <A
7214 HREF="appendix.html#ACTIONSANAT"
7216 > for a brief example on troubleshooting
7239 >, can be defined by combining other actions.
7240 These can in turn be invoked just like the built-in actions.
7241 Currently, an alias name can contain any character except space, tab,
7259 > that you only use <SPAN
7279 Alias names are not case sensitive, and are not required to start with a
7286 > sign, since they are merely textually
7289 > Aliases can be used throughout the actions file, but they <SPAN
7294 defined in a special section at the top of the file!</I
7297 And there can only be one such section per actions file. Each actions file may
7298 have its own alias section, and the aliases defined in it are only visible
7299 within that file.</P
7301 > There are two main reasons to use aliases: One is to save typing for frequently
7302 used combinations of actions, the other one is a gain in flexibility: If you
7303 decide once how you want to handle shops by defining an alias called
7307 >, you can later change your policy on shops in
7314 > place, and your changes will take effect everywhere
7315 in the actions file where the <SPAN
7318 > alias is used. Calling aliases
7319 by their purpose also makes your actions files more readable.</P
7321 > Currently, there is one big drawback to using aliases, though:
7325 >'s built-in web-based action file
7326 editor honors aliases when reading the actions files, but it expands
7327 them before writing. So the effects of your aliases are of course preserved,
7328 but the aliases themselves are lost when you edit sections that use aliases
7331 > Now let's define some aliases...</P
7341 > # Useful custom aliases we can use later.
7343 # Note the (required!) section header line and that this section
7344 # must be at the top of the actions file!
7348 # These aliases just save typing later:
7349 # (Note that some already use other aliases!)
7351 +crunch-all-cookies = +<A
7352 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7353 >crunch-incoming-cookies</A
7355 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7356 >crunch-outgoing-cookies</A
7358 -crunch-all-cookies = -<A
7359 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7360 >crunch-incoming-cookies</A
7362 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7363 >crunch-outgoing-cookies</A
7365 +block-as-image = +block +handle-as-image
7366 allow-all-cookies = -crunch-all-cookies -<A
7367 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7368 >session-cookies-only</A
7370 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
7371 >filter{content-cookies}</A
7374 # These aliases define combinations of actions
7375 # that are useful for certain types of sites:
7378 HREF="actions-file.html#BLOCK"
7381 HREF="actions-file.html#FILTER"
7383 > -crunch-all-cookies -<A
7384 HREF="actions-file.html#FAST-REDIRECTS"
7387 HREF="actions-file.html#HIDE-REFERER"
7390 HREF="actions-file.html#KILL-POPUPS"
7393 HREF="actions-file.html#PREVENT-COMPRESSION"
7394 >prevent-compression</A
7397 shop = -crunch-all-cookies -<A
7398 HREF="actions-file.html#FILTER-ALL-POPUPS"
7399 >filter{all-popups}</A
7401 HREF="actions-file.html#KILL-POPUPS"
7405 # Short names for other aliases, for really lazy people ;-)
7407 c0 = +crunch-all-cookies
7408 c1 = -crunch-all-cookies</PRE
7414 > ...and put them to use. These sections would appear in the lower part of an
7415 actions file and define exceptions to the default actions (as specified further
7429 > # These sites are either very complex or very keen on
7430 # user data and require minimal interference to work:
7433 .office.microsoft.com
7434 .windowsupdate.microsoft.com
7435 # Gmail is really mail.google.com, not gmail.com
7439 # Allow cookies (for setting and retrieving your customer data)
7443 .worldpay.com # for quietpc.com
7446 # These shops require pop-ups:
7448 {-kill-popups -filter{all-popups} -filter{unsolicited-popups}}
7450 .overclockers.co.uk</PRE
7456 > Aliases like <SPAN
7462 > are typically used for
7466 > sites that require more than one action to be disabled
7467 in order to function properly.</P
7475 >8.7. Actions Files Tutorial</A
7478 > The above chapters have shown <A
7479 HREF="actions-file.html"
7480 >which actions files
7481 there are and how they are organized</A
7482 >, how actions are <A
7483 HREF="actions-file.html#ACTIONS"
7486 HREF="actions-file.html#ACTIONS-APPLY"
7490 HREF="actions-file.html#AF-PATTERNS"
7494 HREF="actions-file.html#ALIASES"
7496 >. Now, let's look at an
7504 file and see how all these pieces come together:</P
7511 >8.7.1. default.action</A
7514 >Every config file should start with a short comment stating its purpose:</P
7524 ># Sample default.action file <ijbswa-developers@lists.sourceforge.net></PRE
7530 >Then, since this is the <TT
7534 first section is a special section for internal use that you needn't
7535 change or worry about:</P
7545 >##########################################################################
7546 # Settings -- Don't change! For internal Privoxy use ONLY.
7547 ##########################################################################
7550 for-privoxy-version=3.0</PRE
7556 >After that comes the (optional) alias section. We'll use the example
7557 section from the above <A
7558 HREF="actions-file.html#ALIASES"
7559 >chapter on aliases</A
7561 that also explains why and how aliases are used:</P
7571 >##########################################################################
7573 ##########################################################################
7576 # These aliases just save typing later:
7577 # (Note that some already use other aliases!)
7579 +crunch-all-cookies = +<A
7580 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7581 >crunch-incoming-cookies</A
7583 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7584 >crunch-outgoing-cookies</A
7586 -crunch-all-cookies = -<A
7587 HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
7588 >crunch-incoming-cookies</A
7590 HREF="actions-file.html#CRUNCH-OUTGOING-COOKIES"
7591 >crunch-outgoing-cookies</A
7593 +block-as-image = +block +handle-as-image
7594 mercy-for-cookies = -crunch-all-cookies -<A
7595 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7596 >session-cookies-only</A
7598 HREF="actions-file.html#FILTER-CONTENT-COOKIES"
7599 >filter{content-cookies}</A
7602 # These aliases define combinations of actions
7603 # that are useful for certain types of sites:
7606 HREF="actions-file.html#BLOCK"
7609 HREF="actions-file.html#FILTER"
7611 > -crunch-all-cookies -<A
7612 HREF="actions-file.html#FAST-REDIRECTS"
7615 HREF="actions-file.html#HIDE-REFERER"
7618 HREF="actions-file.html#KILL-POPUPS"
7621 shop = -crunch-all-cookies -<A
7622 HREF="actions-file.html#FILTER-ALL-POPUPS"
7623 >filter{all-popups}</A
7625 HREF="actions-file.html#KILL-POPUPS"
7633 > Now come the regular sections, i.e. sets of actions, accompanied
7634 by URL patterns to which they apply. Remember <SPAN
7639 are disabled when matching starts</I
7641 >, so we have to explicitly
7642 enable the ones we want.</P
7644 > The first regular section is probably the most important. It has only
7653 HREF="actions-file.html#AF-PATTERNS"
7654 >matches all URLs</A
7656 set of actions used in this <SPAN
7664 be applied to all requests as a start</I
7666 >. It can be partly or
7667 wholly overridden by later matches further down this file, or in user.action,
7668 but it will still be largely responsible for your overall browsing
7671 > Again, at the start of matching, all actions are disabled, so there is
7672 no need to disable any actions here. (Remember: a <SPAN
7676 preceding the action name enables the action, a <SPAN
7680 Also note how this long line has been made more readable by splitting it into
7681 multiple lines with line continuation.</P
7691 >##########################################################################
7692 # "Defaults" section:
7693 ##########################################################################
7696 HREF="actions-file.html#DEANIMATE-GIFS"
7700 HREF="actions-file.html#FILTER-HTML-ANNOYANCES"
7701 >filter{html-annoyances}</A
7704 HREF="actions-file.html#FILTER-REFRESH-TAGS"
7705 >filter{refresh-tags}</A
7708 HREF="actions-file.html#FILTER-WEBBUGS"
7712 HREF="actions-file.html#FILTER-IE-EXPLOITS"
7713 >filter{ie-exploits}</A
7716 HREF="actions-file.html#HIDE-FORWARDED-FOR-HEADERS"
7717 >hide-forwarded-for-headers</A
7720 HREF="actions-file.html#HIDE-FROM-HEADER"
7721 >hide-from-header{block}</A
7724 HREF="actions-file.html#HIDE-REFERER"
7725 >hide-referrer{forge}</A
7728 HREF="actions-file.html#PREVENT-COMPRESSION"
7729 >prevent-compression</A
7732 HREF="actions-file.html#SESSION-COOKIES-ONLY"
7733 >session-cookies-only</A
7736 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7737 >set-image-blocker{pattern}</A
7740 / # forward slash will match *all* potential URL patterns.</PRE
7746 > The default behavior is now set.
7749 > The first of our specialized sections is concerned with <SPAN
7753 sites, i.e. sites that require minimum interference, because they are either
7754 very complex or very keen on tracking you (and have mechanisms in place that
7755 make them unusable for people who avoid being tracked). We will simply use
7759 > alias instead of stating the list
7760 of actions explicitly:</P
7770 >##########################################################################
7771 # Exceptions for sites that'll break under the default action set:
7772 ##########################################################################
7774 # "Fragile" Use a minimum set of actions for these sites (see alias above):
7777 .office.microsoft.com # surprise, surprise!
7778 .windowsupdate.microsoft.com
7779 mail.google.com</PRE
7785 > Shopping sites are not as fragile, but they typically
7786 require cookies to log in, and pop-up windows for shopping
7787 carts or item details. Again, we'll use a pre-defined alias:</P
7801 .worldpay.com # for quietpc.com
7812 HREF="actions-file.html#FAST-REDIRECTS"
7816 action, which we enabled per default above, breaks some sites. So disable
7817 it for popular sites where we know it misbehaves:</P
7828 HREF="actions-file.html#FAST-REDIRECTS"
7834 .altavista.com/.*(like|url|link):http
7835 .altavista.com/trans.*urltext=http
7842 > It is important that <SPAN
7846 URLs belong to images, so that <SPAN
7853 be blocked, a substitute image can be sent, rather than an HTML page.
7854 Contacting the remote site to find out is not an option, since it
7855 would destroy the loading time advantage of banner blocking, and it
7856 would feed the advertisers (in terms of money <SPAN
7863 information). We can mark any URL as an image with the <TT
7866 HREF="actions-file.html#HANDLE-AS-IMAGE"
7870 and marking all URLs that end in a known image file extension is a
7881 >##########################################################################
7883 ##########################################################################
7885 # Define which file types will be treated as images, in case they get
7886 # blocked further down this file:
7889 HREF="actions-file.html#HANDLE-AS-IMAGE"
7892 /.*\.(gif|jpe?g|png|bmp|ico)$</PRE
7898 > And then there are known banner sources. They often use scripts to
7899 generate the banners, so it won't be visible from the URL that the
7900 request is for an image. Hence we block them <SPAN
7907 mark them as images in one go, with the help of our
7910 >+block-as-image</TT
7911 > alias defined above. (We could of
7912 course just as well use <TT
7915 HREF="actions-file.html#BLOCK"
7919 HREF="actions-file.html#HANDLE-AS-IMAGE"
7923 Remember that the type of the replacement image is chosen by the
7927 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7928 >set-image-blocker</A
7931 action. Since all URLs have matched the default section with its
7935 HREF="actions-file.html#SET-IMAGE-BLOCKER"
7936 >set-image-blocker</A
7939 action before, it still applies and needn't be repeated:</P
7949 ># Known ad generators:
7954 .ad.*.doubleclick.net
7955 .a.yimg.com/(?:(?!/i/).)*$
7956 .a[0-9].yimg.com/(?:(?!/i/).)*$
7964 > One of the most important jobs of <SPAN
7968 is to block banners. Many of these can be <SPAN
7975 HREF="actions-file.html#FILTER"
7977 >{banners-by-size}</TT
7979 action, which we enabled above, and which deletes the references to banner
7980 images from the pages while they are loaded, so the browser doesn't request
7981 them anymore, and hence they don't need to be blocked here. But this naturally
7982 doesn't catch all banners, and some people choose not to use filters, so we
7983 need a comprehensive list of patterns for banner URLs here, and apply the
7987 HREF="actions-file.html#BLOCK"
7990 > action to them.</P
7992 > First comes many generic patterns, which do most of the work, by
7993 matching typical domain and path name components of banners. Then comes
7994 a list of individual patterns for specific sites, which is omitted here
7995 to keep the example short:</P
8005 >##########################################################################
8006 # Block these fine banners:
8007 ##########################################################################
8009 HREF="actions-file.html#BLOCK"
8019 /.*count(er)?\.(pl|cgi|exe|dll|asp|php[34]?)
8020 /(?:.*/)?(publicite|werbung|rekla(ma|me|am)|annonse|maino(kset|nta|s)?)/
8022 # Site-specific patterns (abbreviated):
8030 > It's quite remarkable how many advertisers actually call their banner
8036 >.com, or call the directory
8037 in which the banners are stored simply <SPAN
8041 generic patterns are surprisingly effective.</P
8043 > But being very generic, they necessarily also catch URLs that we don't want
8044 to block. The pattern <TT
8056 >.nasty-corp.com"</SPAN
8066 >.sourcefroge.net"</SPAN
8076 >l.some-provider.net."</SPAN
8078 well-known exceptions to the <TT
8081 HREF="actions-file.html#BLOCK"
8087 > Note that these are exceptions to exceptions from the default! Consider the URL
8090 >"downloads.sourcefroge.net"</SPAN
8091 >: Initially, all actions are deactivated,
8092 so it wouldn't get blocked. Then comes the defaults section, which matches the
8093 URL, but just deactivates the <TT
8096 HREF="actions-file.html#BLOCK"
8100 action once again. Then it matches <TT
8103 >, an exception to the
8104 general non-blocking policy, and suddenly
8108 HREF="actions-file.html#BLOCK"
8111 > applies. And now, it'll match
8118 HREF="actions-file.html#BLOCK"
8122 applies, so (unless it matches <SPAN
8128 > further down) it ends up
8132 HREF="actions-file.html#BLOCK"
8135 > action applying.</P
8145 >##########################################################################
8146 # Save some innocent victims of the above generic block patterns:
8147 ##########################################################################
8152 HREF="actions-file.html#BLOCK"
8155 adv[io]*. # (for advogato.org and advice.*)
8156 adsl. # (has nothing to do with ads)
8157 adobe. # (has nothing to do with ads either)
8158 ad[ud]*. # (adult.* and add.*)
8159 .edu # (universities don't host banners (yet!))
8160 .*loads. # (downloads, uploads etc)
8168 www.globalintersec.com/adv # (adv = advanced)
8169 www.ugu.com/sui/ugu/adv</PRE
8175 > Filtering source code can have nasty side effects,
8176 so make an exception for our friends at sourceforge.net,
8177 and all paths with <SPAN
8180 > in them. Note that
8184 HREF="actions-file.html#FILTER"
8194 > filters in one fell swoop!</P
8204 ># Don't filter code!
8207 HREF="actions-file.html#FILTER"
8214 .sourceforge.net</PRE
8223 > is of course much more
8224 comprehensive, but we hope this example made clear how it works.</P
8232 >8.7.2. user.action</A
8235 > So far we are painting with a broad brush by setting general policies,
8236 which would be a reasonable starting point for many people. Now,
8237 you might want to be more specific and have customized rules that
8238 are more suitable to your personal habits and preferences. These would
8239 be for narrowly defined situations like your ISP or your bank, and should
8243 >, which is parsed after all other
8244 actions files and hence has the last word, over-riding any previously
8245 defined actions. <TT
8255 > place for your personal settings, since
8259 > is actively maintained by the
8263 > developers and you'll probably want
8264 to install updated versions from time to time.</P
8266 > So let's look at a few examples of things that one might typically do in
8280 ># My user.action file. <fred@example.com></PRE
8287 HREF="actions-file.html#ALIASES"
8289 > are local to the actions
8290 file that they are defined in, you can't use the ones from
8294 >, unless you repeat them here:</P
8304 ># Aliases are local to the file they are defined in.
8305 # (Re-)define aliases for this file:
8309 # These aliases just save typing later, and the alias names should
8310 # be self explanatory.
8312 +crunch-all-cookies = +crunch-incoming-cookies +crunch-outgoing-cookies
8313 -crunch-all-cookies = -crunch-incoming-cookies -crunch-outgoing-cookies
8314 allow-all-cookies = -crunch-all-cookies -session-cookies-only
8315 allow-popups = -filter{all-popups} -kill-popups
8316 +block-as-image = +block +handle-as-image
8317 -block-as-image = -block
8319 # These aliases define combinations of actions that are useful for
8320 # certain types of sites:
8322 fragile = -block -crunch-all-cookies -filter -fast-redirects -hide-referrer -kill-popups
8323 shop = -crunch-all-cookies allow-popups
8325 # Allow ads for selected useful free sites:
8327 allow-ads = -block -filter{banners-by-size} -filter{banners-by-link}
8329 # Alias for specific file types that are text, but might have conflicting
8330 # MIME types. We want the browser to force these to be text documents.
8331 handle-as-text = -<A
8332 HREF="actions-file.html#FILTER"
8335 HREF="actions-file.html#CONTENT-TYPE-OVERWRITE"
8336 >content-type-overwrite{text/plain}</A
8338 HREF="actions-file.html#FORCE-TEXT-MODE"
8341 HREF="actions-file.html#HIDE-CONTENT-DISPOSITION"
8342 >hide-content-disposition</A
8349 > Say you have accounts on some sites that you visit regularly, and
8350 you don't want to have to log in manually each time. So you'd like
8351 to allow persistent cookies for these sites. The
8354 >allow-all-cookies</TT
8355 > alias defined above does exactly
8356 that, i.e. it disables crunching of cookies in any direction, and the
8357 processing of cookies to make them only temporary.</P
8367 >{ allow-all-cookies }
8377 > Your bank is allergic to some filter, but you don't know which, so you disable them all:</P
8388 HREF="actions-file.html#FILTER"
8391 .your-home-banking-site.com</PRE
8397 > Some file types you may not want to filter for various reasons:</P
8407 ># Technical documentation is likely to contain strings that might
8408 # erroneously get altered by the JavaScript-oriented filters:
8413 # And this stupid host sends streaming video with a wrong MIME type,
8414 # so that Privoxy thinks it is getting HTML and starts filtering:
8416 stupid-server.example.com/</PRE
8422 > Example of a simple <A
8423 HREF="actions-file.html#BLOCK"
8425 > action. Say you've
8426 seen an ad on your favourite page on example.com that you want to get rid of.
8427 You have right-clicked the image, selected <SPAN
8429 >"copy image location"</SPAN
8431 and pasted the URL below while removing the leading http://, into a
8435 > section. Note that <TT
8439 > need not be specified, since all URLs ending in
8443 > will be tagged as images by the general rules as set
8444 in default.action anyway:</P
8455 HREF="actions-file.html#BLOCK"
8458 www.example.com/nasty-ads/sponsor\.gif
8459 another.example.net/more/junk/here/</PRE
8465 > The URLs of dynamically generated banners, especially from large banner
8466 farms, often don't use the well-known image file name extensions, which
8467 makes it impossible for <SPAN
8471 the file type just by looking at the URL.
8474 >+block-as-image</TT
8475 > alias defined above for
8477 Note that objects which match this rule but then turn out NOT to be an
8478 image are typically rendered as a <SPAN
8480 >"broken image"</SPAN
8482 browser. Use cautiously.</P
8492 >{ +block-as-image }
8502 > Now you noticed that the default configuration breaks Forbes Magazine,
8503 but you were too lazy to find out which action is the culprit, and you
8504 were again too lazy to give <A
8508 you just used the <TT
8511 > alias on the site, and
8518 > -- it worked. The <TT
8522 aliases disables those actions that are most likely to break a site. Also,
8523 good for testing purposes to see if it is <SPAN
8527 that is causing the problem or not. We later find other regular sites
8528 that misbehave, and add those to our personalized list of troublemakers:</P
8547 > You like the <SPAN
8550 > text replacements in <TT
8554 but it is disabled in the distributed actions file.
8555 So you'd like to turn it on in your private,
8556 update-safe config, once and for all:</P
8567 HREF="actions-file.html#FILTER-FUN"
8570 / # For ALL sites!</PRE
8576 > Note that the above is not really a good idea: There are exceptions
8577 to the filters in <TT
8581 really shouldn't be filtered, like code on CVS->Web interfaces. Since
8585 > has the last word, these exceptions
8586 won't be valid for the <SPAN
8589 > filtering specified here.</P
8591 > You might also worry about how your favourite free websites are
8592 funded, and find that they rely on displaying banner advertisements
8593 to survive. So you might want to specifically allow banners for those
8594 sites that you feel provide value to you:</P
8616 > has been aliased to
8620 HREF="actions-file.html#BLOCK"
8627 HREF="actions-file.html#FILTER-BANNERS-BY-SIZE"
8628 >filter{banners-by-size}</A
8634 HREF="actions-file.html#FILTER-BANNERS-BY-LINK"
8635 >filter{banners-by-link}</A
8639 > Invoke another alias here to force an over-ride of the MIME type <TT
8641 > application/x-sh</TT
8642 > which typically would open a download type
8643 dialog. In my case, I want to look at the shell script, and then I can save
8644 it should I choose to.</P
8664 > is generally the best place to define
8665 exceptions and additions to the default policies of
8669 >. Some actions are safe to have their
8670 default policies set here though. So let's set a default policy to have a
8674 > image as opposed to the checkerboard pattern for
8684 > of course matches all URL
8685 paths and patterns:</P
8696 HREF="actions-file.html#SET-IMAGE-BLOCKER"
8697 >set-image-blocker{blank}</A
8712 SUMMARY="Footer navigation table"
8741 HREF="filter-file.html"
8751 >The Main Configuration File</TD