Have you ever faced a situation as a frontend developer where you needed to show a demo to your product manager, and something was broken in the API response? Or, a production bug where you were block

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Chrome DevTools has a built-in Content Overriding feature that lets frontend developers mock API responses and override response headers locally without any backend changes. This covers three practical scenarios: fixing incorrect API responses, validating UI states that require specific data conditions, and bypassing CORS errors by injecting the necessary headers. Overrides are stored as local files and can be shared with teammates, applied globally across all endpoints, or selectively disabled.

How to Override API Responses and Headers in Chrome DevTools: A Step-by-Step Guide

Problem 2: Validating a UI Scenario Without Backend Changes

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