chromium/chrome/test/data/extensions/api_test/content_scripts/ntp/manifest.json

{
  "name": "New Tab Page Injector",
  "version": "0.1",
  "manifest_version": 2,
  "description": "Injects in the NTP",
  "content_scripts": [{
    "matches": ["*://*/*"],
    "js": ["script.js"],
    "run_at": "document_end"
  }],
  "background": {"scripts": ["background.js"], "persistent": true},
  "permissions": ["tabs", "*://*/*"]
}