TypeSpeed

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "TypeSpeed",
  "description": "Tells you how fast you type",
  "version": "0.0.0.1",
  "browser_action": {
    "default_icon": "icon.png",
    "default_popup": "popup.html"
  },
  "background": {
    "page": "background.html",
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "all_frames": true
    }
  ],
  "permissions": [
    "activeTab",
    "tabs"
  ]
}