Examine source code of HideIt

{
  "manifest_version": 2,
  "name": "HideIt",
  "description": "Extention to hide element on a webpage",
  "version": "0.3resigned1",
  "default_locale": "en",
  "applications": {
    "gecko": {
      "strict_min_version": "56.0",
      "id": "{6b233bdf-9154-4576-aa31-ee16023599cf}"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "menus",
    "activeTab"
  ],
  "icons": {
    "16": "icons/logo-16.png",
    "32": "icons/logo-32.png",
    "48": "icons/logo-48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "checkmouse.js"
      ]
    }
  ]
}