Examine source code of WaMe Hopper

{
  "manifest_version": 2,
  "name": "WaMe Hopper",
  "version": "1.1",
  "description": "Easily open WhatsApp chats from selected phone numbers in Firefox.",
  "icons": {
    "48": "icons/icon48.png",
    "96": "icons/icon96.png"
  },
  "permissions": [
    "contextMenus",
    "tabs",
    "storage",
    "*://restcountries.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0462cf61-ba8d-41e9-9f72-21d27e5ee91f}"
    }
  }
}