Examine source code of Better Search for Google

{
  "manifest_version": 2,
  "name": "Better Search for Google",
  "description": "Block content farms, spam sites, and low-quality results from Google Search. Customize filters for cleaner, better results.",
  "version": "1.0.0",
  "icons": {
    "16": "icon/16.png",
    "32": "icon/32.png",
    "48": "icon/48.png",
    "96": "icon/96.svg",
    "128": "icon/128.svg"
  },
  "permissions": [
    "declarativeNetRequest",
    "declarativeNetRequestWithHostAccess",
    "storage",
    "tabs",
    "*://www.google.com/*",
    "*://www.google.co.uk/*",
    "*://www.google.ca/*",
    "*://www.google.com.au/*",
    "*://www.google.de/*",
    "*://www.google.fr/*",
    "*://www.google.es/*",
    "*://www.google.it/*",
    "*://www.google.nl/*",
    "*://www.google.pl/*",
    "*://www.google.jp/*",
    "*://www.google.com.br/*",
    "*://www.google.in/*",
    "*://www.google.com.mx/*",
    "*://www.google.co.nz/*",
    "*://www.google.com.ar/*",
    "*://www.google.com.sa/*",
    "*://www.google.se/*",
    "*://www.google.no/*",
    "*://www.google.dk/*",
    "*://www.google.fi/*",
    "*://www.google.co.za/*",
    "*://www.google.com.pk/*",
    "*://www.google.com.eg/*",
    "*://www.google.com.vn/*",
    "*://www.google.co.id/*",
    "*://www.google.com.my/*",
    "*://www.google.com.sg/*",
    "*://www.google.co.kr/*",
    "*://www.google.com.tw/*",
    "*://www.google.com.hk/*",
    "*://www.google.com.ph/*",
    "*://www.google.com.ng/*",
    "*://www.google.com.gh/*",
    "*://www.google.co.ke/*",
    "*://www.google.com.bd/*"
  ],
  "omnibox": {
    "keyword": "f"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "dashboard.html",
    "open_in_tab": true
  },
  "declarative_net_request": {
    "rule_resources": [
      {
        "id": "ruleset_1",
        "enabled": true,
        "path": "rules.json"
      }
    ]
  },
  "web_accessible_resources": [
    "page-inject.js",
    "search.html"
  ],
  "commands": {
    "toggle-extension": {
      "suggested_key": {
        "default": "Ctrl+Shift+S",
        "mac": "Command+Shift+S"
      },
      "description": "Toggle Custom Search on/off"
    },
    "search-web": {
      "description": "Search Web with filters (set key in chrome://extensions/shortcuts)"
    },
    "search-images": {
      "description": "Search Images with filters (set key in chrome://extensions/shortcuts)"
    },
    "search-videos": {
      "description": "Search Videos with filters (set key in chrome://extensions/shortcuts)"
    },
    "search-news": {
      "description": "Search News with filters (set key in chrome://extensions/shortcuts)"
    }
  },
  "browser_action": {
    "default_title": "Better Search",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.google.ca/*",
        "*://www.google.co.id/*",
        "*://www.google.co.ke/*",
        "*://www.google.co.kr/*",
        "*://www.google.co.nz/*",
        "*://www.google.co.uk/*",
        "*://www.google.co.za/*",
        "*://www.google.co.za/*",
        "*://www.google.com.ar/*",
        "*://www.google.com.au/*",
        "*://www.google.com.bd/*",
        "*://www.google.com.br/*",
        "*://www.google.com.eg/*",
        "*://www.google.com.gh/*",
        "*://www.google.com.hk/*",
        "*://www.google.com.mx/*",
        "*://www.google.com.my/*",
        "*://www.google.com.ng/*",
        "*://www.google.com.ph/*",
        "*://www.google.com.pk/*",
        "*://www.google.com.sa/*",
        "*://www.google.com.sg/*",
        "*://www.google.com.tw/*",
        "*://www.google.com.vn/*",
        "*://www.google.com/*",
        "*://www.google.de/*",
        "*://www.google.dk/*",
        "*://www.google.es/*",
        "*://www.google.fi/*",
        "*://www.google.fr/*",
        "*://www.google.in/*",
        "*://www.google.it/*",
        "*://www.google.jp/*",
        "*://www.google.nl/*",
        "*://www.google.no/*",
        "*://www.google.pl/*",
        "*://www.google.se/*"
      ],
      "run_at": "document_idle",
      "css": [
        "content-scripts/content.css"
      ],
      "js": [
        "content-scripts/content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "custom-search@bettersearch.net",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}