Examine source code of HTTPtoHTTPS

{
  "manifest_version": 2,
  "name": "HTTPtoHTTPS",
  "version": "1.2resigned1",
  "description": "Widget converts http prefix to https on the current page and refreshes it. Also works vice versa from 1.0.2. version.",
  "icons": {
    "64": "icons/64.png"
  },
  "permissions": [
    "tabs",
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/slika1.png",
    "default_title": "Click to add 's' to http"
  },
  "background": {
    "scripts": [
      "main.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "jid0-ad08RZ08iNQBNTcg20ZWy84a73I@jetpack"
    }
  }
}