Introducing InterceptX: The Ultimate Modern Alternative to ModHeader

Introducing InterceptX: The Ultimate Modern Alternative to ModHeader for HTTP Modifications As web developers, API engineers, and security auditors, we spend a significant portion of our time inspecting and tweaking HTTP traffic. For years, extensions like ModHeader have been the go-to utility for modifying request and response headers on the fly. However, as the browser extension landscape transitions fully to Manifest V3 —bringing stricter security, better performance, and tighter permission rules—many developers are looking for a modern, lightweight, and local-first alternative. Enter InterceptX . What is InterceptX? InterceptX is a high-performance, compact Chrome extension designed to give you complete control over browser network requests. Built from the ground up on Manifest V3 using the declarative declarativeNetRequest API, it is fast, secure, and preserves your battery life by running lightweight matching rules inside the browser engine itself. Whether you need to bypass CORS policies, simulate mobile user-agents, override security headers, or redirect API endpoints to your local development server, InterceptX does it all with a premium, glassmorphic UI. Key Features at a Glance If you are familiar with ModHeader, you will feel right at home with InterceptX—but with several modern upgrades: 1. Request & Response Header Modifications Inject, append, or strip headers on outgoing requests or incoming responses: Set : Override an existing header or add a new one (e.g., setting custom auth tokens or Origin ). Append : Append values to headers like Accept or Cookie . Remove : Completely strip headers (e.g., testing behaviors when header keys are omitted). 2. URL Redirections Need to test API endpoints or redirect files? InterceptX features a built-in regex redirect engine (using RE2 syntax). You can redirect matching patterns and even use capture groups (e.g., redirecting https://api.production.com/(.*) to http://localhost:3000/\1 ). 3. Granular URL & Domain Fil