Examine source code of Keep+

{
  "manifest_version": 2,
  "name": "Keep+",
  "version": "1.0",
  "description": "Notes taking application.",
  "content_security_policy": "script-src 'self' 'unsafe-eval'; object-src 'self'",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "browser_action": {
    "default_icon": "icons/icon-48.png",
    "default_title": "Keep+",
    "default_popup": "index.html"
  },
  "web_accessible_resources": [
    "index.html",
    "keep-plus.html"
  ]
}