Synch with 2.4.x

<p>The [B] flag instructs <directive

module="mod_rewrite">RewriteRule</directive> to escape non-alphanumeric

characters before applying the transformation.</p>

<p>In 2.4.10 and later, you can limit the escaping to specific characters

<p>In 2.4.26 and later, you can limit the escaping to specific characters

in backreferences by listing them: <code>[B=#?;]</code>. Note: The space

character can be used in the list of characters to escape, but it cannot be

the last character in the list.</p>

module="mod_rewrite">RewriteRule</directive> to escape the space character

in a backreference to %20 rather than '+'. Useful when the backreference

will be used in the path component rather than the query string.</p>

<p>This flag is available in version 2.4.26 and later.</p>

</section>

<section id="flag_c"><title>C|chain</title>