Hide what browser is being used

Do you want to apply it to one URI? like this?

 user-agent from: http://www.useragentstring.com/pages/Safari/

when HTTP_REQUEST {
  if { [HTTP::uri] equals "/x/y/z" } {
   switch -glob [string tolower [HTTP::header User-Agent]] {
      "*safari*" {
         HTTP::header replace "User-Agent" "my custom user-agent string"
      }
   }
  }
}