Examine source code of Image Info

{
  "manifest_version": 2,
  "name": "Image Info",
  "version": "1.0.1",
  "description": "Shows image resolution and size on mouse hover.",
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "jquery-3.2.1.min.js",
        "content.js"
      ],
      "all_frames": true
    }
  ],
  "options_ui": {
    "page": "options.html"
  },
  "icons": {
    "48": "icon.svg",
    "96": "icon.svg"
  },
  "permissions": [
    "storage",
    "http://*/*",
    "https://*/*"
  ]
}