Examine source code of Detectube for Firefox

{
  "manifest_version": 2,
  "name": "Detectube for Firefox",
  "version": "1.0",
  "description": "Adds a browser action icon to the toolbar. Click the button or press Ctrl+Shift+F to query Detectube for the current url.",
  "homepage_url": "https://www.detectube.com",
  "icons": {
    "48": "icons/detectube-48.png",
    "96": "icons/detectube-96.png"
  },
  "permissions": [
    "tabs",
    "webRequest",
    "webRequestBlocking",
    "https://www.detectube.com/processlink/"
  ],
  "browser_action": {
    "default_icon": "icons/detectube-32.png",
    "default_title": "Detectube"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "commands": {
    "activate": {
      "suggested_key": {
        "default": "Ctrl+Shift+F"
      },
      "description": "Activate the extension"
    }
  }
}