Examine source code of PasswordGen

{
  "manifest_version": 2,
  "name": "PasswordGen",
  "description": "__MSG_extensionDescription__",
  "version": "3.1resigned1",
  "author": "Daniel Kubica",
  "default_locale": "en",
  "homepage_url": "https://github.com/DanKub/PasswordGen",
  "icons": {
    "64": "icons/passwordgen-64.png"
  },
  "applications": {
    "gecko": {
      "id": "passwordgen@passwordgen.local"
    }
  },
  "browser_action": {
    "browser_style": true,
    "default_icon": "icons/passwordgen-64.png",
    "default_title": "PasswordGen",
    "default_popup": "popup/popup.html"
  },
  "options_ui": {
    "page": "options/options.html"
  },
  "permissions": [
    "storage",
    "tabs",
    "downloads",
    "clipboardWrite",
    "https://publicsuffix.org/list/public_suffix_list.dat"
  ],
  "background": {
    "scripts": [
      "background/background.js"
    ]
  }
}