rid) {
            xGrid.insertBefore(debugLine, firstCell);
        } else {
            xGrid.appendChild(debugLine);
        }
    }

    handleClassMutation(mutationList) {
        mutationList.forEach(mutation => {
            if (mutation.type === 'attributes' && mutation.attributeName === 'class') {
                const xGrid = mutation.target;
                this.createDebugLine(xGrid);
            }
        });
    }

}

document.addEventListener('DOMContentLoaded', () => {
    new xGridVisualAid