Examine source code of Screen Tester Pro

{
  "manifest_version": 3,
  "name": "Screen Tester Pro",
  "version": "1.0.1",
  "description": "Professional display calibration tool. Test for dead pixels, backlight bleed, color accuracy, gamma, geometry and more - in one click.",
  "author": "BeYor",
  "homepage_url": "https://beyor.dev",
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "action": {
    "default_title": "Screen Tester Pro",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "tabs"
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "screen-tester.html",
        "screen-tester.js"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "screen-tester-pro@beyor",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}