rule "Drop unsupported browsers errors"
when
    has_field("user_agent_browser_name_and_version")
    AND ($message.user_agent_browser_name_and_version == "MSIE 10.0"
    OR $message.user_agent_browser_name_and_version == "MSIE 9.0"
    OR $message.user_agent_browser_name_and_version == "Firefox/16.0"
    OR $message.user_agent_browser_name_and_version == "Firefox/22.0"
    OR $message.user_agent_browser_name_and_version == "Firefox/27.0"
    OR $message.user_agent_browser_name_and_version == "Firefox/28.0"
    OR $message.user_agent_browser_name_and_version == "Firefox/30.0"
    OR $message.user_agent_browser_name_and_version == "Firefox/31.0"
    OR $message.user_agent_browser_name_and_version == "Firefox/32.0"
    OR $message.user_agent_browser_name_and_version == "Chrome/21.0.1180.89"
    OR $message.user_agent_browser_name_and_version == "Chrome/23.0.1271.64"
    OR $message.user_agent_browser_name_and_version == "Chrome/27.0.1453.110"
    OR $message.user_agent_browser_name_and_version == "Chrome/29.0.1547.66"
    OR $message.user_agent_browser_name_and_version == "Chrome/30.0.0.0"
    OR $message.user_agent_browser_name_and_version == "Chrome/32.0.1700.107"
    OR $message.user_agent_browser_name_and_version == "Chrome/36.0.1985.143"
    OR $message.user_agent_browser_name_and_version == "Chrome/50.0.2661.102"
    OR $message.user_agent_browser_name_and_version == "Chrome/52.0.2743.91"
    OR $message.user_agent_browser_name_and_version == "Safari/8536.25")
then
    drop_message();
end