Examine source code of TabJam

{
  "manifest_version": 3,
  "name": "TabJam",
  "version": "1.0.9",
  "description": "Supported sites reuse tabs to save you time!",
  "permissions": [
    "activeTab",
    "storage"
  ],
  "background": {
    "scripts": [
      "dist/background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "contact@oddsjam.com"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "dist/sites.js"
      ]
    },
    {
      "matches": [
        "https://localhost:3000/*",
        "https://dev.oddsjam.com/*",
        "https://oddsjam.com/*"
      ],
      "js": [
        "dist/tabmania.js"
      ]
    }
  ],
  "action": {
    "default_popup": "public/popup.html",
    "default_icon": {
      "16": "images/icon16.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    }
  },
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  }
}