Function createMirrorCanvas

src/platforms/wasm/compiler/index.ts:1213–1234

* Creates a hidden mirror canvas to receive frames from worker for main-thread recording * @param {number} width - Canvas width * @param {number} height - Canvas height * @returns {HTMLCanvasElement} Mirror canvas

(width, height)

 * @returns {HTMLCanvasElement} Mirror canvas
 */
function createMirrorCanvas(width, height) {
  console.log('Creating mirror canvas:', width, 'x', height);

  // Create canvas element
  const canvas = document.createElement('canvas');
  canvas.id = 'mirror-canvas';
  canvas.width = width;
  canvas.height = height;

  // Hide canvas (not displayed, only used for recording)
  canvas.style.position = 'absolute';
  canvas.style.left = '-9999px';
  canvas.style.top = '-9999px';
  canvas.style.pointerEvents = 'none';

  // Add to DOM (required for MediaRecorder)
  document.body.appendChild(canvas);

  console.log('Mirror canvas created and added to DOM');

  return canvas;
}

/**
 * Sets up message listener for frame updates from worker