chromium/chrome/test/data/extensions/back_forward_cache/background_page/manifest.json

{
  "name": "Background Page Extension",
  "version": "1.0",
  "manifest_version": 2,
  "description": "A minimal extension for testing purposes.",
  "background": {
    "scripts": ["background.js"],
    "persistent": false
  },
  "permissions": ["*://a.com/*", "*://b.com/*"]
}