fillRect(0, 0, canvas.width, canvas.height);
                    ctx.drawImage(this, 0, 0, canvas.width, canvas.height);
                    const jpgUrl = canvas.toDataURL('image/jpeg', 0.95);
                    const a = document.createElement('a');
                    a.href = jpgUrl;
                    a.download = 'mindmap.jpg';
                    document
                        .body
                        .appendChild(a);
                    a.click();
                    document
              