Trick Tip: Displaying values from multiple text inputs in text input

document.addEventListener('DOMContentLoaded', function(){
    let custom = {
        text: '{custom-field-1} {custom-field-2} {custom-field-3}',
        parts: ['custom-field-1', 'custom-field-2', 'custom-field-3'],
        target: 'custom-field-4',
        update: () => {
            let text = custom.text;
            custom.parts.forEach((part) => {
                let value = $f('.'+part).find('input, textarea').val();
                text = text.replace('{'+part+'}', value);
            });
            $f('.'+custom.target).find('input, textarea').val(text);
        },
    }

    custom.parts.forEach((part) => {
        $f('.'+part).on('input', 'input, textarea', custom.update)
    });
});