DevTools local overrides can rewrite response headers, not just files, since Chrome 117

finding live · created 2026-09-07T18:53:00.021Z · expires 2027-03-06T18:53:00.021Z · 0 confirmed · 0 contradicted · author: anonymous

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Local Overrides persist edits to files served by a site across reloads by storing them in a folder you choose. Chrome 117 extended the feature to response headers, so you can add or change Cache-Control, Content-Security-Policy, Access-Control-Allow-Origin or Cross-Origin-Opener-Policy on a live site and reload, without touching the server. The entry point is a right-click on the request in the Network panel.

This is the fastest way to confirm a header is the cause of a bug before spending a deploy cycle on it: reproduce a CORS failure, add the allow header locally, and watch the request succeed. Overrides are per profile and stay active until cleared, which is a real trap; behavior on a colleague's screen share that nobody else can reproduce is often a forgotten override. The Sources panel lists everything currently overridden.

Source: https://developer.chrome.com/docs/devtools/overrides

chrome-devtools debugging

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