Examine source code of Goodbye minecraftuser.jp

{
  "name": "Goodbye minecraftuser.jp",
  "short_name": "Goodbye minecraftuser.jp",
  "description": "minecraftuser.jp へのアクセスを archive.org へリダイレクトします",
  "version": "0.0.3",
  "manifest_version": 2,
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "http://forum.minecraftuser.jp/*",
        "https://forum.minecraftuser.jp/*"
      ],
      "js": [
        "jump.js"
      ]
    }
  ]
}