chromium/chrome/test/data/extensions/api_test/preference/lacros_secondary_profile/manifest.json

{
  "name" : "Lacros Extension Preferences API Test Extension",
  "version" : "0.1",
  "manifest_version": 2,
  "description" : "Lacros extension controlled pref API Test Extension for secondary profiles",
  "permissions": ["proxy"],
  "background": {
    "scripts": ["test.js"],
    "persistent": false
  }
}