Examine source code of Celestus Interface++

{
  "manifest_version": 2,
  "name": "Celestus Interface++",
  "version": "1.4",
  "description": "Ajoute et améliore des menus du jeux par navigateur celestus.",
  "icons": {
    "48": "icons/icon.png",
    "96": "icons/icon.png"
  },
  "permissions": [
    "storage",
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_popup": "popup.html",
    "default_title": "Celestus Interface++"
  },
  "content_scripts": [
    {
      "matches": [
        "*://horizon.celestus.fr/*"
      ],
      "js": [
        "celestusInterface.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{63075945-c40f-4bdf-a4eb-691350fee428}"
    }
  }
}