How can i bypass the unique id problem in multi-state boxes?

Perhaps this one…

$w.onReady(()=>{
    $w('#myDropdown').onChange(()=>{
        let stateValue = $w('#myDropdown').value
        $w('#myMultiBox1').changeState(stateValue)
        $w('#myMultiBox2').changeState(stateValue)
    })
})