Examine source code of Emacs-keybinding

{
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "developer": {
    "name": "Bernd Wachter"
  },
  "manifest_version": 2,
  "name": "Emacs-keybinding",
  "description": "An addon for using Firefox with Emacs keybinding",
  "version": "0.3.2",
  "homepage_url": "https://github.com/bwachter/emacs-keybinding",
  "author": "Wang Kai",
  "browser_specific_settings": {
    "gecko": {
      "id": "{e95dd474-674a-4768-9965-8360529685a5}",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "activeTab",
    "history",
    "search",
    "storage",
    "tabs",
    "topSites"
  ],
  "optional_permissions": [
    "<all_urls>"
  ],
  "browser_action": {
    "default_title": "Emacs keybinding",
    "default_popup": "/popup/minibuffer.html",
    "default_icon": {
      "19": "icons/emacs-19.png",
      "38": "icons/emacs-38.png"
    }
  },
  "icons": {
    "48": "icons/emacs-48.png",
    "96": "icons/emacs-96.png"
  },
  "options_ui": {
    "page": "options.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "search.js",
        "keybindings.js"
      ]
    }
  ]
}