Examine source code of Better Twitch Resolution Label

{
  "manifest_version": 3,
  "name": "Better Twitch Resolution Label",
  "version": "3.0",
  "description": "Adds a custom resolution label to the Twitch player and optional FPS indicator.",
  "icons": {
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "action": {
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.twitch.tv/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "storage"
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "icons/eye.png"
      ],
      "matches": [
        "*://www.twitch.tv/*"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{39777ce2-a1e6-4497-8d27-7041b518b753}",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}