Examine source code of Webp Watcher

{
  "manifest_version": 2,
  "name": "Webp Watcher",
  "author": "Vhou-Atroph",
  "version": "1.0.0",
  "description": "Automatically adds &format=original to certain image files on wikia sites.",
  "homepage_url": "https://github.com/Vhou-Atroph/webp_watcher",
  "icons": {
    "48": "icons/webp-48.png",
    "96": "icons/webp-96.png"
  },
  "content_scripts": [
    {
      "exclude_matches": [
        "*://*/*&format=original"
      ],
      "matches": [
        "*://static.wikia.nocookie.net/*.png*",
        "*://static.wikia.nocookie.net/*.jp*g*",
        "*://static.wikia.nocookie.net/*.gif*"
      ],
      "js": [
        "watcher.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{cae10dc8-fafc-40bc-840c-51391885699e}"
    }
  }
}