Examine source code of Histogram Viewer

{
  "manifest_version": 2,
  "name": "__MSG_extensionName__",
  "version": "3.0.1resigned1",
  "homepage_url": "__MSG_extensionHomepage__",
  "description": "__MSG_extensionDescription__",
  "applications": {
    "gecko": {
      "id": "histogramviewer@davidfichtmueller.de"
    }
  },
  "developer": {
    "name": "David Fichtmueller"
  },
  "icons": {
    "48": "icons/histogramviewer.png"
  },
  "permissions": [
    "*://*/*",
    "file:///*",
    "activeTab",
    "contextMenus",
    "storage"
  ],
  "default_locale": "en",
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "background": {
    "scripts": [
      "histogramviewer.js"
    ]
  }
}