Apps similar to Header Override include Requestly, which is open source with a free version. Other options are OpenHeader and modheader. In total there are three API Clients like Header Override for Mac, Windows, Linux and the web.
Requestly is a lightweight proxy available as a browser extension & desktop app to intercept & modify network requests. Using Requestly you can Modify Headers, Redirect Url, Mock API response, Delay/Throttle requests, etc.
United States
Lightweight Chrome extension lets you add, modify, or remove HTTP request and response headers securely using declarativeNetRequest. Open source with no ads, tracking, or telemetry, minimal permissions, supports multiple profiles, per-URL filters, and import/export.
ModHeader is a powerful browser extension that provides users with complete control over HTTP(S) headers. By allowing you to modify, add, or remove headers in a simple and user-friendly interface.
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