After enabling the 5G Firewall Protection I see in my .htaccess:
... RedirectMatch 403 (\=\'|\=\%27|/\'/?|\)\.css\()$ ...
But according to the http://perishablepress.com/5g-blacklist-2013/ the line should be:
RedirectMatch 403 (\=\\\'|\=\\%27|/\\\'/?|\)\.css\()$
I have no idea what version is correct.
BTW. this plugin is a MUST HAVE. Thanks for the great work.