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| |
| <html> |
| <head> |
| <meta name="viewport" content="width=device-width, initial-scale=1"> |
| <title>Add Head</title> |
| <link rel="stylesheet" href="doc.css"> |
| </head> |
| <body> |
| <!--#include virtual="_header.html" --> |
| |
| |
| <div id=content> |
| <h1>Add Head</h1> |
| |
| |
| |
| <h2>Configuration</h2> |
| <p> |
| The 'Add Head' filter is enabled by specifying: |
| <dl> |
| <dt>Apache:<dd><pre class="prettyprint" |
| >ModPagespeedEnableFilters add_head</pre> |
| <dt>Nginx:<dd><pre class="prettyprint" |
| >pagespeed EnableFilters add_head;</pre> |
| </dl> |
| <p> |
| in the configuration file, but it is also enabled automatically by several |
| other filters, including combine_heads, move_css_to_head, and |
| add_instrumentation. |
| </p> |
| |
| <h2>Description</h2> |
| <p> |
| The 'Add Head' filter is very simple: it adds a head to the document if it |
| encounters a <body> tag before finding a <head> tag. |
| </p> |
| <p> |
| For example, if the HTML document looks like this: |
| </p> |
| <pre class="prettyprint"> |
| <html> |
| <body> |
| <div class="blue yellow big bold"> |
| Hello, world! |
| </div> |
| </body> |
| </html> |
| </pre> |
| <p> |
| Then PageSpeed will rewrite it into: |
| </p> |
| <pre class="prettyprint"> |
| <html> |
| <head> |
| </head> |
| <body> |
| <div class="blue yellow big bold"> |
| Hello, world! |
| </div> |
| </body> |
| </html> |
| </pre> |
| |
| <h2>Note</h2> |
| <p> |
| This filter exists primarily to ensure that other filters have a place |
| to insert new tags that needs to be in the head, or that trigger on |
| the closing-tag for a head to perform some other action. |
| </p> |
| |
| <h2>Risks</h2> |
| <p> |
| This filter is considered minimal risk. |
| </p> |
| |
| |
| </div> |
| <!--#include virtual="_footer.html" --> |
| </body> |
| </html> |
