Examine source code of Twitch Chat Screenshot

{
  "manifest_version": 2,
  "name": "Twitch Chat Screenshot",
  "version": "2.0.3",
  "description": "Adds a screenshot button to Twitch chat messages and copies them to the clipboard.",
  "browser_specific_settings": {
    "gecko": {
      "id": "twitchchatscreenshot@local",
      "strict_min_version": "109.0"
    }
  },
  "permissions": [
    "<all_urls>",
    "tabs",
    "clipboardWrite",
    "storage",
    "nativeMessaging"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.twitch.tv/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_icon": "icons/icon.svg",
    "default_title": "Twitch Chat Screenshot",
    "default_popup": "popup.html"
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  }
}