Examine source code of justsayit

{
  "manifest_version": 2,
  "name": "justsayit",
  "version": "1.3.1",
  "description": "An extension for Firefox that enables voice dictation on any website. Web Dictate can be used with any Whisper API service (including locally hosted).",
  "author": "Failmode",
  "homepage_url": "https://github.com/mbailey/justsayit",
  "browser_specific_settings": {
    "gecko": {
      "id": "justsayit@example.com",
      "strict_min_version": "79.0"
    }
  },
  "privacy_policy": "privacy_policy.md",
  "icons": {
    "16": "icons/sayit-16.png",
    "32": "icons/sayit-32.png",
    "48": "icons/sayit-48.png",
    "96": "icons/sayit-96.png"
  },
  "permissions": [
    "activeTab",
    "storage",
    "<all_urls>",
    "tabs",
    "notifications",
    "contextMenus"
  ],
  "browser_action": {
    "default_icon": {
      "16": "icons/sayit-16.png",
      "32": "icons/sayit-32.png"
    },
    "default_title": "justsayit"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ]
    }
  ],
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  }
}