+9.2. The Pre-defined Filters
+
+The distribution default.filter file contains a selection of pre-defined
+filters for your convenience:
+
+js-annoyances
+
+ The purpose of this filter is to get rid of particularly annoying
+ JavaScript abuse. To that end, it
+
+ + replaces JavaScript references to the browser's referrer information
+ with the string "Not Your Business!". This compliments the
+ hide-referrer action on the content level.
+
+ + removes the bindings to the DOM's unload event which we feel has no
+ right to exist and is responsible for most "exit consoles", i.e. nasty
+ windows that pop up when you close another one.
+
+ + removes code that causes new windows to be opened with undesired
+ properties, such as being full-screen, non-resizable, without location,
+ status or menu bar etc.
+
+js-events
+
+ This is a very radical measure. It removes virtually all JavaScript event
+ bindings, which means that scripts can not react to user actions such as
+ mouse movements or clicks, window resizing etc, anymore.
+
+ We strongly discourage using this filter as a default since it breaks many
+ legitimate scripts. It is meant for use only on extra-nasty sites (should
+ you really need to go there).
+
+html-annoyances
+
+ This filter will undo many common instances of HTML based abuse.
+
+ The BLINK and MARQUEE tags are neutralized (yeah baby!), and browser
+ windows will be created as resizable (as of course they should be!), and
+ will have location, scroll and menu bars -- even if specified otherwise.
+
+content-cookies
+
+ Most cookies are set in the HTTP dialogue, where they can be intercepted by
+ the crunch-incoming-cookies and crunch-outgoing-cookies actions. But web
+ sites increasingly make use of HTML meta tags and JavaScript to sneak
+ cookies to the browser on the content level.
+
+ This filter disables HTML and JavaScript code that reads or sets cookies.
+ Use it wherever you would also use the cookie crunch actions.
+
+refresh tags
+
+ Disable any refresh tags if the interval is greater than nine seconds (so
+ that redirections done via refresh tags are not destroyed). This is useful
+ for dial-on-demand setups, or for those who find this HTML feature
+ annoying.
+
+unsolicited-popups
+
+ This filter attempts to prevent only "unsolicited" pop-up windows from
+ opening, yet still allow pop-up windows that the user has explicitly chosen
+ to open. It was added in version 3.0.1, as an improvement over earlier such
+ filters.
+
+ Technical note: The filter works by redefining the window.open JavaScript
+ function to a dummy function during the loading and rendering phase of each
+ HTML page access, and restoring the function afterwards.
+
+all-popups
+
+ Attempt to prevent all pop-up windows from opening. Note this should be
+ used with more discretion than the above, since it is more likely to break
+ some sites that require pop-ups for normal usage. Use with caution.
+
+img-reorder
+
+ This is a helper filter that has no value if used alone. It makes the
+ banners-by-size and banners-by-link (see below) filters more effective and
+ should be enabled together with them.
+
+banners-by-size
+
+ This filter removes image tags purely based on what size they are.
+ Fortunately for us, many ads and banner images tend to conform to certain
+ standardized sizes, which makes this filter quite effective for ad
+ stripping purposes.
+
+ Occasionally this filter will cause false positives on images that are not
+ ads, but just happen to be of one of the standard banner sizes.
+
+banners-by-link
+
+ This is an experimental filter that attempts to kill any banners if their
+ URLs seem to point to known or suspected click trackers. It is currently
+ not of much value and is not recommended for use by default.
+
+webbugs
+
+ Webbugs are small, invisible images (technically 1X1 GIF images), that are
+ used to track users across websites, and collect information on them. As an
+ HTML page is loaded by the browser, an embedded image tag causes the
+ browser to contact a third-party site, disclosing the tracking information
+ through the requested URL and/or cookies for that third-party domain,
+ without the use ever becoming aware of the interaction with the third-party
+ site. HTML-ized spam also uses a similar technique to verify email
+ addresses.
+
+ This filter removes the HTML code that loads such "webbugs".
+
+tiny-textforms
+
+ A rather special-purpose filter that can be used to enlarge textareas
+ (those multi-line text boxes in web forms) and turn off hard word wrap in
+ them. It was written for the sourceforge.net tracker system where such
+ boxes are a nuisance, but it can be handy on other sites, too.
+
+ It is not recommended to use this filter as a default.
+
+jumping-windows
+
+ Many consider windows that move, or resize themselves to be abusive. This
+ filter neutralizes the related JavaScript code. Note that some sites might
+ not display or behave as intended when using this filter.
+
+frameset-borders
+
+ Some web designers seem to assume that everyone in the world will view
+ their web sites using the same browser brand and version, screen resolution
+ etc, because only that assumption could explain why they'd use static frame
+ sizes, yet prevent their frames from being resized by the user, should they
+ be too small to show their whole content.
+
+ This filter removes the related HTML code. It should only be applied to
+ sites which need it.
+
+demoronizer
+
+ Many Microsoft products that generate HTML use non-standard extensions
+ (read: violations) of the ISO 8859-1 aka Latin-1 character set. This causes
+ those HTML documents to display with errors on standard-compliant
+ platforms.
+
+ This filter translates the MS-only characters into Latin-1 equivalents. It
+ is not necessary when using MS products, and will cause corruption of all
+ documents that use 8-bit character sets other than Latin-1. It's mostly
+ worthwhile for Europeans on non-MS platforms, if wierd garbage characters
+ sometimes appear on some pages.
+
+shockwave-flash
+
+ A filter for shockwave haters. As the name suggests, this filter strips
+ code out of web pages that is used to embed shockwave flash objects.
+
+quicktime-kioskmode
+
+ Change HTML code that embeds Quicktime objects so that kioskmode, which
+ prevents saving, is disabled.
+
+fun
+
+ Text replacements for subversive browsing fun. Make fun of your favorite
+ Monopolist or play buzzword bingo.
+
+crude-parental
+
+ A demonstration-only filter that shows how Privoxy can be used to delete
+ web content on a keyword basis.
+
+ie-exploits
+
+ A collection of text replacements to disable malicious HTML and JavaScript
+ code that exploits known security holes in Internet Explorer.
+
+ Presently, it only protects against Nimda and a cross-site scripting bug,
+ and would need active maintenance to provide more substantial protection.
+
+site-specifics
+
+ Some web sites have very specific problems, the cure for which doesn't
+ apply anywhere else, or could even cause damage on other sites.
+
+ This is a collection of such site-specific cures which should only be
+ applied to the sites they were intended for, which is what the supplied
+ default.action file does. Users shouldn't need to change anything regarding
+ this filter.
+
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+