Examine source code of FPL Classic Design

{
  "manifest_version": 2,
  "name": "FPL Classic Design",
  "version": "3.0",
  "description": "Reverts Fantasy Premier League to the classic design",
  "author": "FPL",
  "browser_specific_settings": {
    "gecko": {
      "id": "{39f347b1-3dc9-4986-95fe-9ce5d419926e}",
      "strict_min_version": "79.0"
    }
  },
  "icons": {
    "48": "icon-48.png",
    "96": "icon-96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://fantasy.premierleague.com/*"
      ],
      "css": [
        "fpl-classic.css"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_action": {
    "default_icon": "icon-48.png",
    "default_title": "FPL Classic Design",
    "default_popup": "popup.html"
  },
  "permissions": [
    "storage",
    "tabs"
  ]
}