Examine source code of fERP

{
  "manifest_version": 2,
  "name": "fERP",
  "description": "Automates the process of filling up feedback form in ERP for IIT KGP students",
  "homepage_url": "https://github.com/proffapt/fERP",
  "version": "1.9.0",
  "permissions": [
    "activeTab",
    "*://erp.iitkgp.ac.in/IIT_ERP*/*",
    "https://gymkhana.iitkgp.ac.in/api/ecs"
  ],
  "browser_action": {
    "default_title": "fERP",
    "default_popup": "main.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "proffapt@pm.me"
    }
  },
  "icons": {
    "16": "images/fERP16.png",
    "32": "images/fERP32.png",
    "64": "images/fERP64.png",
    "128": "images/fERP128.png"
  }
}