Examine source code of Mainospalkki

{
  "description": "Adds customizable ad-bar to a website",
  "manifest_version": 2,
  "name": "Mainospalkki",
  "version": "1.1.1",
  "homepage_url": "https://github.com/teemu-mjr",
  "icons": {
    "48": "icons/icon-48.png"
  },
  "browser_action": {
    "default_icon": "icons/icon-32.png",
    "theme_icons": [
      {
        "light": "icons/icon-32-light.png",
        "dark": "icons/icon-32.png",
        "size": 32
      }
    ],
    "default_title": "Mainospalkki",
    "default_popup": "popup/popup.html"
  },
  "web_accessible_resources": [
    ""
  ],
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{3103e5fe-2699-45e1-94af-c05ee66f7825}"
    }
  }
}