Examine source code of SpotFrame

{
  "manifest_version": 3,
  "name": "SpotFrame",
  "version": "1.0.0",
  "description": "Dim the page and spotlight the selection with a glowing frame for focused reading.",
  "permissions": [
    "contextMenus",
    "activeTab",
    "scripting"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_title": "SpotFrame",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "64": "icons/icon64.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "64": "icons/icon64.png",
    "128": "icons/icon128.png"
  },
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'; base-uri 'self'; connect-src 'self'; img-src 'self' data:; style-src 'self';"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "spotframe@example.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "strict_min_version": "142.0"
    }
  }
}