ModHeader V1 ✨ by modheader.app ✅

ModHeader V1 ✨ by modheader.app ✅ – The Ultimate Firefox Add-on for Modifying HTTP Headers

ModHeader V1 ✨ by modheader.app ✅ is a powerful Firefox Add-on for modifying, adding, editing, removing, and overriding HTTP request headers and HTTP response headers. Whether you're a web developer, frontend engineer, backend developer, QA tester, DevOps engineer, security researcher, API developer, or IT professional, ModHeader V1 ✨ by modheader.app ✅ provides an easy way to inspect and customize network requests directly from your browser.

Modify headers without changing your application code. Instantly override User-Agent, Referer, Origin, Cookie, Authorization, Accept, Accept-Language, Cache-Control, Host, X-Forwarded-For, X-Requested-With, Content-Type, Content-Length, Connection, DNT, Sec-Fetch headers, custom headers, and many more.

ModHeader V1 ✨ by modheader.app ✅ is built for modern web development and API testing.

Perfect for Developers.

Key Features: • Modify HTTP request headers • Modify HTTP response headers • Add new request headers • Add new response headers • Edit existing headers • Remove unwanted headers • Override request headers • Override response headers • Replace header values • Disable headers • Enable headers with one click • Create reusable header profiles • Switch between profiles instantly • Apply rules based on URL patterns • Enable or disable rules per website • Import and export configurations • Backup and restore profiles • Lightweight and fast • Privacy focused • No unnecessary permissions

Use ModHeader V1 ✨ by modheader.app ✅ to: • Test REST APIs • Test GraphQL APIs • Debug HTTP requests • Debug HTTP responses • Simulate different browsers • Change User-Agent strings • Override Referer headers • Modify Origin headers • Edit Authorization tokens • Inject Bearer tokens • Test JWT authentication • Add API keys • Modify cookies • Test CORS behavior • Debug CORS issues • Test CDN configurations • Test reverse proxies • Test load balancers • Test cache behavior • Test localization using Accept-Language • Test mobile websites • Test desktop websites • Test browser compatibility • Simulate different devices • Simulate crawlers and bots • Debug authentication flows • Test staging environments • Test production APIs safely

Common Use Cases: • HTTP header editor • Request header modifier • Response header modifier • Header manager • User-Agent switcher • Referer changer • Cookie editor • Origin modifier • Authorization header editor • API testing tool • REST API testing • GraphQL testing • Network debugging • Web development • Frontend development • Backend development • Website debugging • Browser debugging • CORS testing • Security testing • Penetration testing • QA automation • Software testing • Web application testing

Supports Common Headers: • User-Agent • Referer • Origin • Cookie • Authorization • Accept • Accept-Encoding • Accept-Language • Cache-Control • Pragma • Connection • Upgrade-Insecure-Requests • DNT • Host • Content-Type • Content-Length • X-Requested-With • X-Forwarded-For • X-Real-IP • X-API-Key • Custom headers • Response headers • Request headers

Why Choose ModHeader V1 ✨ by modheader.app ✅? • Clean and intuitive interface • Fast rule matching • Easy profile management • Reliable request interception • Powerful header modification engine • Designed for developers • Works with modern websites • Regular updates • High performance • Easy to learn • Advanced features for professionals

Whether you're debugging an API, testing authentication, modifying request headers, overriding response headers, changing User-Agent, editing cookies, troubleshooting CORS, or building modern web applications, ModHeader V1 ✨ by modheader.app ✅ is the Firefox Add-on that helps you work faster and more efficiently.