on inventory click:
    if name of player's inventory
every 1 minute:
    loop all players:
        if {timespend::%loop-player%} is not set:
            set {timespend::%loop-player%} to 1
        else:
            add 1 to {timespend::%loop-player%}
            
command /timespend:
    aliases: ts
    trigger:
        if {timespend::%player%} is not set:
            set {timespend::%player%} to 0
            
        set {_hours} to {timespend::%player%} / 60
        set {_hours} to rounded down {_hours}
            
        open chest with 9 rows named "&5&lCzas spędzony na serwerze"
        set slot 42 of player's inventory to blue stained glass pane named "&7Czas spędzony na serwerze: &a{_hours}"