/ip firewall mangle
add action=mark-connection chain=prerouting comment=Discord_RTC \
    connection-bytes=102 connection-mark=no-mark content="\00\00\00\00\00\00\
    \00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\
    \00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\
    \00\00\00\00\00\00\00\00\00\00" dst-address-type=!local \
    in-interface-list=LAN new-connection-mark=conn_isp_openvpn port=\
    50000-50100 protocol=udp