Examine source code of UniSE Page

{
  "manifest_version": 3,
  "name": "UniSE Page",
  "version": "1.0",
  "description": "Open a meta search engine page.",
  "permissions": [
    "activeTab"
  ],
  "action": {
    "default_icon": {
      "16": "./UniSE.png",
      "32": "./UniSE.png",
      "48": "./UniSE.png",
      "128": "./UniSE.png"
    },
    "default_title": "Open UniSE Page"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "unise-page-launcher@trailw.com",
      "strict_min_version": "109.0"
    }
  },
  "icons": {
    "16": "./UniSE.png",
    "32": "./UniSE.png",
    "48": "./UniSE.png",
    "128": "./UniSE.png"
  }
}