Examine source code of Tel-Linker US

{
  "manifest_version": 2,
  "name": "Tel-Linker US",
  "version": "1.0.2",
  "description": "Automatically detect and link US phone numbers to your dialer app.",
  "author": "Subculture Networks, LLC",
  "homepage_url": "https://software.subculturenetworks.com/tel-linker-us",
  "permissions": [
    "<all_urls>",
    "activeTab",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_title": "Tel-Linker US",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "tel-linker-us@subculturenetworks.com",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "icons": {
    "512": "icons/icon.png"
  }
}