A mapping of PHP regular expressions to replacement values which are executed on all blog HTML after WordPress finishes emitting the entire page. The pattern and replacement behavior is in the manner of preg_replace().
The following example removes all HTML comments in the first pattern, and causes a favicon (with any filename extension) to be loaded from another domain in the second pattern:
#<!--.*?-->#s =>
#\bsrc="/(favicon\..*)"# => src="http://mycdn.somewhere.com/$1"
Eu am incercat
#<!--.*?-->#s =>
/^[ \t]*[\r\n]+/m =>
Asta #<!--.*?-->#s => elimina comentarile
Si asta /^[ \t]*[\r\n]+/m => scoate linile goale
Acum vreau sa comprime codul css din pagina ? puteti sa ma ajutati