allow returning custom chains from on() function
allow returning custom chains from on() function

svisystem/atk4,xepan/atk4,xepan/atk4,atk4/atk4,svisystem/atk4,atk4/atk4,samratcis/atk4,samratcis/atk4,atk4/atk4,xepan/atk4,svisystem/atk4,atk4/atk4,samratcis/atk4