Examine source code of Minimal New Page

{
  "background": {
    "scripts": [
      "assets/script.js"
    ]
  },
  "browser_action": {
    "default_icon": "assets/icon.png"
  },
  "chrome_url_overrides": {
    "newtab": "blank.html"
  },
  "chrome_settings_overrides": {
    "homepage": "blank.html"
  },
  "content_security_policy": "script-src 'self'; default-src 'self'",
  "description": "Override the new tab page with a minimal clock",
  "icons": {
    "16": "assets/icon16.png",
    "48": "assets/icon48.png",
    "128": "assets/icon128.png"
  },
  "manifest_version": 2,
  "name": "Minimal New Page",
  "version": "0.3"
}