Examine source code of ScrollMeter

{
  "manifest_version": 2,
  "minimum_chrome_version": "20",
  "name": "ScrollMeter",
  "description": "This extension displays the statistics on scrolled distance for current site",
  "version": "0.0.3",
  "default_locale": "en",
  "icons": {
    "16": "/img/icon16.png",
    "48": "/img/icon48.png",
    "128": "/img/icon128.png"
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "page_action": {
    "default_icon": "/img/icon32bw.png",
    "default_popup": "popup.html",
    "default_title": "ScrollMeter Options"
  },
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "content_scripts": [
    {
      "all_frames": false,
      "css": [
        "css/scrollmeter.css"
      ],
      "js": [
        "js/scrollmeter.js"
      ],
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "tabs",
    "http://*/*",
    "https://*/*",
    "storage",
    "webRequest"
  ]
}