in src/js/client/helpers.ts [41:48]
function removeClass(el: HTMLElement, className: string) {
if (el.classList) {
el.classList.remove(className);
} else {
el.className = el.className.replace(new RegExp('(^|\\b)' +
className.split(' ').join('|') + '(\\b|$)', 'gi'), ' ');
}
}