Examine source code of del0

{
  "name": "del0",
  "version": "0.0.1",
  "manifest_version": 2,
  "browser_action": {
    "default_popup": "action.html",
    "default_icon": "icon.png"
  },
  "content_scripts": [
    {
      "css": [
        "styles.css"
      ],
      "matches": [
        "https://outlook.live.com/*"
      ]
    }
  ],
  "icons": {
    "128": "icon.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{73c058fb-1a2d-4396-bb35-54133e6fc855}"
    }
  }
}