Examine source code of Pop-Up Dictionary

{
  "manifest_version": 2,
  "name": "Pop-Up Dictionary",
  "version": "4.2.4resigned1",
  "description": "Pop-Up Dictionary on selected word",
  "icons": {
    "48": "icons/bookicon48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content/popupdict-common.js",
        "content/popupdict-content.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "lib/popupdict-db.js",
      "background/popupdict-background.js"
    ]
  },
  "options_ui": {
    "page": "settings/settings.html",
    "open_in_tab": true
  },
  "applications": {
    "gecko": {
      "id": "popupdict@rickyexample.org"
    }
  },
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "browser_style": false,
    "default_icon": {
      "48": "icons/button-48d.png"
    },
    "default_title": "Pop-Up Dictionary",
    "default_popup": "popup/popup.html"
  }
}