Examine source code of new-tab pinned

{
  "manifest_version": 2,
  "homepage_url": "https://github.com/dodying/newtab-pinned",
  "name": "__MSG_extName__",
  "version": "0.0.3resigned1",
  "default_locale": "en",
  "description": "__MSG_extDesc__",
  "icons": {
    "16": "images/logo-16.png",
    "48": "images/logo-48.png"
  },
  "browser_action": {
    "default_icon": {
      "16": "images/logo-16.png",
      "48": "images/logo-48.png"
    }
  },
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "commands": {
    "close-tab": {
      "suggested_key": {
        "default": "Alt+W"
      }
    },
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Alt+P"
      }
    }
  },
  "permissions": [
    "tabs",
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d53394ae-8137-4aa8-9389-ac2a97c7cdca}"
    }
  }
}