[
  {
    "search": "let context = canvas.getContext(\"2d\");",
    "replace": ""
  },
  {
    "search": "const SQ = squareSize = 20;",
    "replace": "const SQ = squareSize = 20;\n\n    if (!canvas) {\n        throw new Error('Canvas element not found');\n    }\n\n    let context = canvas.getContext(\"2d\");\n\n    if (!context) {\n        throw new Error('Canvas context not found');\n    }"
  }
]