Examine source code of Light Switch Grid

{
  "manifest_version": 2,
  "name": "Light Switch Grid",
  "description": "A grid of switches where every flip drags its neighbours along. Work out the order that leaves the whole board dark, or ask for the shortest sequence when a pattern refuses to fall.",
  "version": "8.2.4",
  "browser_specific_settings": {
    "gecko": {
      "id": "{51384a4e-e088-43f8-abf0-f556e8d40d2f}",
      "strict_min_version": "101.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "32": "assets/icon-32.png",
    "48": "assets/icon-48.png",
    "64": "assets/icon-64.png",
    "96": "assets/icon-96.png",
    "128": "assets/icon-128.png"
  },
  "browser_action": {
    "default_title": "Light Switch Grid",
    "default_popup": "popup.html",
    "default_icon": {
      "32": "assets/icon-32.png",
      "48": "assets/icon-48.png",
      "64": "assets/icon-64.png"
    }
  },
  "permissions": [
    "storage"
  ]
}