Examine source code of Ghost Grammarly

{
  "description": "Applies a fix to the Ghost Koenig editor allowing Grammarly to work properly",
  "manifest_version": 2,
  "name": "Ghost Grammarly",
  "version": "1.0",
  "icons": {
    "256": "icons/ghost.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/ghost.png",
    "default_title": "Ghost Grammarly",
    "default_popup": "popup/index.html"
  }
}