Examine source code of Googlepanel Lite WE

{
  "manifest_version": 2,
  "name": "Googlepanel Lite WE",
  "version": "1.1resigned1",
  "version_name": "1.0 alpha",
  "description": "Googlepanel Lite WE, resurrected to use Webextensions, compatible with Firefox 57+.",
  "icons": {
    "48": "icon.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "contentscript.js"
      ]
    }
  ],
  "permissions": [
    "contextMenus",
    "activeTab",
    "tabs"
  ],
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "Googlepanel Lite WE",
    "default_popup": "popup.htm",
    "browser_style": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{796dd796-d98f-44f8-b672-1673cac5db7c}"
    }
  }
}