attributeChangedCallback(attr, _oldValue, newValue) {
			if (this.$$r) return;
			attr = this.$$g_p(attr);
			this.$$d[attr] = get_custom_element_value(attr, newValue, this.$$p_d, 'toProp');
			this.$$c?.$set({ [attr]: this.$$d[attr] });
		}
@param {string} attr
@param {string} _oldValue
@param {string} newValue