<panel color='0' context='settings'>
    <label id='%{id}.L' margin='0,3,0,0'>%{name}: %{value}%{postfix}</label>
    <trackbar 
        value='%{value}' min='%{min}' max='%{max}' step='%{step}' tooltip='%{tooltip}'
        consumer='function(x) update_setting(x, "%{id}", "%{name}", "%{postfix}") end'/>
</panel>
