set isLocked(value) {
        if (this._isLocked === value) {
            return;
        }
        this._isLocked = value;
        this._hoverContainer.classList.toggle('locked', this._isLocked);
    }
Whether the hover is "locked" by holding the alt/option key. When locked, the hover will not
hide and can be hovered regardless of whether the `hideOnHover` hover option is set.