Examine source code of Pull Requests Counter

{
  "manifest_version": 2,
  "author": "Renuo AG",
  "name": "Pull Requests Counter",
  "description": "This extension shows the number of Pull Requests assigned to you.",
  "version": "1.4.1resigned1",
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_action": {
    "default_icon": "icon.png",
    "theme_icons": [
      {
        "light": "icon-light.png",
        "dark": "icon.png",
        "size": 32
      }
    ]
  },
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "background": {
    "scripts": [
      "extension.js"
    ]
  },
  "permissions": [
    "activeTab",
    "https://api.github.com/",
    "alarms",
    "storage",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "pull-request-counter@renuo.ch",
      "strict_min_version": "57.0"
    }
  }
}