Examine source code of Simple Gmail Screen

{
  "manifest_version": 2,
  "name": "Simple Gmail Screen",
  "short_name": "SGScreen",
  "description": "__MSG_extDescription__",
  "version": "0.10.1",
  "default_locale": "en",
  "icons": {
    "16": "image/icon.16.png",
    "48": "image/icon.48.png",
    "128": "image/icon.128.png"
  },
  "permissions": [
    "storage"
  ],
  "web_accessible_resources": [
    "lib/jquery-3.1.0.min.js",
    "css/style.css",
    "css/bulma.min.css"
  ],
  "background": {
    "scripts": [
      "lib/jquery-3.1.0.min.js",
      "utils.js",
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "https://mail.google.com/*"
      ],
      "js": [
        "lib/jquery-3.1.0.min.js",
        "utils.js",
        "content.js"
      ],
      "css": [
        "css/style.css"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_action": {
    "default_icon": "image/icon.128.png",
    "default_popup": "popup.html"
  },
  "options_page": "options.html",
  "browser_specific_settings": {
    "gecko": {
      "id": "@simple-gmail-screen",
      "strict_min_version": "53.0"
    }
  }
}