Examine source code of Airstory

{
  "manifest_version": 2,
  "name": "Airstory",
  "description": "Capture research and use it in your writing - no matter where you write online.",
  "version": "2.3.1",
  "browser_action": {
    "default_icon": {
      "16": "images/icons/16.png",
      "24": "images/icons/24.png",
      "32": "images/icons/32.png",
      "64": "images/icons/64.png"
    },
    "default_popup": "html/popup.html",
    "default_title": "Airstory"
  },
  "applications": {
    "gecko": {
      "id": "addon@airstory.co",
      "strict_min_version": "57.0"
    }
  },
  "background": {
    "scripts": [
      "dist/background.min.js"
    ]
  },
  "icons": {
    "16": "images/icons/16.png",
    "48": "images/icons/48.png",
    "128": "images/icons/128.png"
  },
  "options_ui": {
    "page": "html/options.html",
    "chrome_style": true
  },
  "permissions": [
    "<all_urls>",
    "contextMenus",
    "cookies",
    "storage",
    "unlimitedStorage"
  ],
  "web_accessible_resources": [
    "images/*",
    "html/*"
  ]
}