THE SMART TRICK OF WINBOX THAT NOBODY IS DISCUSSING

/ip firewall filter include chain=enter link-state=founded,relevant action=settle for comment="take founded,similar"; insert chain=enter relationship-state=invalid action=drop; add chain=input in-interface=ether1 protocol=icmp motion=accept remark="enable ICMP"; add chain=input in-interface=ether1 protocol=tcp port=8291 action=acknowledge remark="l