Examine source code of Flow Playground Enhancer

{
  "name": "Flow Playground Enhancer",
  "version": "0.0.4.1",
  "description": "This extension is used to add some missing functionality to Flow Playground",
  "permissions": [
    "activeTab",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://play.onflow.org/*"
      ],
      "js": [
        "contentScript.js"
      ],
      "css": [
        "flow-dark-theme.css"
      ]
    }
  ],
  "web_accessible_resources": [
    "*.svg"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "starkaindustries@gmail.com"
    }
  },
  "icons": {
    "16": "images/flow_icon_16.png",
    "32": "images/flow_icon_32.png",
    "64": "images/flow_icon_64.png",
    "128": "images/flow_icon_128.png"
  },
  "manifest_version": 2
}