in src/define/Advert.ts [180:191]
async updateExtraSlotClasses(...newClasses: string[]): Promise<void> {
const classesToRemove = this.extraNodeClasses.filter(
(c) => !newClasses.includes(c),
);
await fastdom.mutate(() => {
this.node.classList.remove(...classesToRemove);
this.node.classList.add(...newClasses);
});
this.extraNodeClasses = newClasses;
}