Units Converter for 750+ physical units

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "Units Converter for 750+ physical units",
  "description": "Converts hundreds of international and historical physical measurement units",
  "version": "1.0",
  "manifest_version": 2,
  "background": {
    "persistent": false,
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "units.png",
    "default_title": "Units Converter"
  },
  "commands": {
    "_execute_browser_action": {
      "suggested_key": {
        "default": "Ctrl+Shift+L",
        "mac": "MacCtrl+Shift+L"
      },
      "description": "Opens Units Converter"
    }
  }
}