Examine source code of FPL Time Adjuster

{
  "manifest_version": 2,
  "name": "FPL Time Adjuster",
  "description": "Changes time on FPL site to local timezone",
  "version": "1.2resigned1",
  "browser_action": {
    "default_icon": "icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://fantasy.premierleague.com/*"
      ],
      "js": [
        "fpltime.js"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{0c7660e8-f15b-4f68-9526-d2986887b290}"
    }
  }
}