Examine source code of NoobPrice

{
  "manifest_version": 2,
  "name": "NoobPrice",
  "version": "1.0",
  "description": "Compare preços de jogos da Steam automaticamente!",
  "permissions": [
    "activeTab",
    "tabs",
    "storage",
    "http://localhost:3000/*",
    "https://api.isthereanydeal.com/*",
    "<all_urls>"
  ],
  "web_accessible_resources": [
    "icon-16.png",
    "icon-48.png",
    "icon-128.png"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icon-16.png",
      "48": "icon-48.png",
      "128": "icon-128.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://store.steampowered.com/app/*"
      ],
      "js": [
        "content.js",
        "chart.js",
        "inject-button.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "noobprice@seusite.com",
      "strict_min_version": "91.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}