Examine source code of Link Shooter

{
  "manifest_version": 2,
  "name": "Link Shooter",
  "version": "1.0",
  "description": "Toggle Link Shooter mode to aim and shoot links on any page. Overlay canvas + scoring.",
  "icons": {
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content_script.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "storage",
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{6adcc55e-c3cd-4ca9-a036-51ab18d4e847}"
    }
  }
}