MeasureIt!

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "background": {
    "scripts": [
      "jquery.min.js",
      "backgroundMeasureIt.js"
    ]
  },
  "browser_action": {
    "default_icon": "off.png",
    "default_title": "MeasureIt"
  },
  "content_scripts": [
    {
      "all_frames": false,
      "css": [
        "styleMeasureIt.css"
      ],
      "js": [
        "measureIt.js"
      ],
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "run_at": "document_idle"
    }
  ],
  "description": "MeasureIt is useful app for measurement width and height of webpages. Measure it in pixels.",
  "manifest_version": 2,
  "name": "MeasureIt!",
  "permissions": [
    "activeTab",
    "http://*/*",
    "https://*/*"
  ],
  "version": "1.2.4",
  "icons": {
    "48": "ico_48.png",
    "128": "ico_128.png"
  }
}