Examine source code of SCRIN.IO

{
  "manifest_version": 2,
  "name": "SCRIN.IO",
  "version": "2.6",
  "author": "Rodion Nikolaev",
  "homepage_url": "https://scrin.io",
  "description": "Browser extension for scrin.io service",
  "icons": {
    "128": "images/icon.png"
  },
  "browser_action": {
    "browser_style": true,
    "default_icon": {
      "128": "images/icon.png"
    },
    "default_title": "SCRIN.IO",
    "default_popup": "extension.html"
  },
  "background": {
    "persistent": true,
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "*://scrin.io/*",
    "storage"
  ]
}