+>"+fast-redirects"</SPAN
+></A
+> action,
+ it is then processed. Unwanted parts of the requested URL are stripped.
+ </P
+></LI
+><LI
+><P
+> Now the rest of the client browser's request headers are processed. If any
+ of these match any of the relevant actions (e.g. <A
+HREF="actions-file.html#HIDE-USER-AGENT"
+><SPAN
+CLASS="QUOTE"
+>"+hide-user-agent"</SPAN
+></A
+>,
+ etc.), headers are suppressed or forged as determined by these actions and
+ their parameters.
+ </P
+></LI
+><LI
+><P
+> Now the web server starts sending its response back (i.e. typically a web page and related
+ data).
+ </P
+></LI
+><LI
+><P
+> First, the server headers are read and processed to determine, among other
+ things, the MIME type (document type) and encoding. The headers are then
+ filtered as determined by the
+ <A
+HREF="actions-file.html#CRUNCH-INCOMING-COOKIES"
+><SPAN
+CLASS="QUOTE"
+>"+crunch-incoming-cookies"</SPAN
+></A
+>,
+ <A
+HREF="actions-file.html#SESSION-COOKIES-ONLY"
+><SPAN
+CLASS="QUOTE"
+>"+session-cookies-only"</SPAN
+></A
+>,
+ and <A
+HREF="actions-file.html#DOWNGRADE-HTTP-VERSION"
+><SPAN
+CLASS="QUOTE"
+>"+downgrade-http-version"</SPAN
+></A
+>
+ actions.
+ </P
+></LI
+><LI
+><P
+> If the <A
+HREF="actions-file.html#KILL-POPUPS"
+><SPAN
+CLASS="QUOTE"
+>"+kill-popups"</SPAN
+></A
+>
+ action applies, and it is an HTML or JavaScript document, the popup-code in the
+ response is filtered on-the-fly as it is received.
+ </P
+></LI
+><LI
+><P
+> If a <A
+HREF="actions-file.html#FILTER"
+><SPAN
+CLASS="QUOTE"
+>"+filter"</SPAN
+></A
+>
+ or <A
+HREF="actions-file.html#DEANIMATE-GIFS"
+><SPAN
+CLASS="QUOTE"
+>"+deanimate-gifs"</SPAN
+></A
+>
+ action applies (and the document type fits the action), the rest of the page is
+ read into memory (up to a configurable limit). Then the filter rules (from
+ <TT
+CLASS="FILENAME"
+>default.filter</TT
+> and any other filter files) are
+ processed against the buffered content. Filters are applied in the order
+ they are specified in one of the filter files. Animated GIFs, if present,
+ are reduced to either the first or last frame, depending on the action
+ setting.The entire page, which is now filtered, is then sent by
+ <SPAN
+CLASS="APPLICATION"
+>Privoxy</SPAN
+> back to your browser.
+ </P
+><P
+> If neither <A
+HREF="actions-file.html#FILTER"
+><SPAN
+CLASS="QUOTE"
+>"+filter"</SPAN
+></A
+>
+ or <A
+HREF="actions-file.html#DEANIMATE-GIFS"
+><SPAN
+CLASS="QUOTE"
+>"+deanimate-gifs"</SPAN
+></A
+>
+ matches, then <SPAN
+CLASS="APPLICATION"
+>Privoxy</SPAN
+> passes the raw data through
+ to the client browser as it becomes available.
+ </P
+></LI
+><LI
+><P
+> As the browser receives the now (possibly filtered) page content, it
+ reads and then requests any URLs that may be embedded within the page
+ source, e.g. ad images, stylesheets, JavaScript, other HTML documents (e.g.
+ frames), sounds, etc. For each of these objects, the browser issues a new
+ request. And each such request is in turn processed as above. Note that a
+ complex web page may have many such embedded URLs.
+ </P
+></LI
+></UL
+></P
+></DIV
+><DIV
+CLASS="SECT2"
+><H2
+CLASS="SECT2"
+><A
+NAME="ACTIONSANAT"
+></A
+>14.4. Anatomy of an Action</H2
+><P
+> The way <SPAN
+CLASS="APPLICATION"
+>Privoxy</SPAN
+> applies
+ <A
+HREF="actions-file.html#ACTIONS"
+>actions</A
+> and <A
+HREF="actions-file.html#FILTER"
+>filters</A
+>
+ to any given URL can be complex, and not always so