Examine source code of Tunescribers Quick Quote

{
  "manifest_version": 2,
  "name": "Tunescribers Auto Redirect",
  "version": "1.0",
  "description": "Quickly start a quote on Tunescribers by sending the current tab's URL.",
  "browser_specific_settings": {
    "gecko": {
      "id": "info@tunescribers.com",
      "strict_min_version": "109.0"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "tabs",
    "activeTab",
    "storage",
    "https://www.tunescribers.com/*",
    "https://www.youtube.com/*",
    "https://soundcloud.com/*",
    "https://open.spotify.com/*"
  ],
  "background": {
    "scripts": [
      "script/background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "index.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.tunescribers.com/*"
      ],
      "js": [
        "script/content.js"
      ]
    },
    {
      "matches": [
        "https://www.youtube.com/*",
        "https://soundcloud.com/*",
        "https://open.spotify.com/*"
      ],
      "js": [
        "script/notify.js"
      ]
    }
  ]
}