Current date and time.

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "Current date and time.",
  "short_name": "Current Time.",
  "description": "Extension to show the current date and time.",
  "version": "0.1",
  "browser_action": {
    "default_title": "Current date and time.",
    "default_icon": "icon.png",
    "default_popup": "popup.html"
  },
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  }
}