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Preview of Network Interceptor

Network Interceptor by Dheeraj Kumar

Intercept, mock, redirect, block, delay, and modify network requests โ€” no proxy or backend changes needed.

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Extension Metadata

About this extension
Network Interceptor gives developers full control over network requests
directly in the browser. Set up rules to mock, redirect, block, delay,
or modify requests โ€” without touching your backend or configuring a proxy.

โ”€โ”€ RULE TYPES โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€

Mock Return a custom response body and status code for any
fetch or XHR request.

Redirect Transparently forward a request to a different URL,
preserving the original method and headers.

Block Cancel matching requests outright.

Delay Slow down requests by a configurable number of
milliseconds to simulate latency.

Modify Headers Add, set, or remove request and response headers
on matching requests.

Modify Query Params Add, replace, or remove URL query parameters
without editing your source code.

Redirect JS Serve a local or alternate script in place of a
remote JavaScript file.


โ”€โ”€ MATCHING OPTIONS โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€

Match URLs by exact string, contains, wildcard (*), or full regex.
Filter by HTTP method (GET, POST, PUT, DELETE, etc.) or match any.


โ”€โ”€ HOW IT WORKS โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€

Rules are applied in real time โ€” no page reload required after
toggling. A subtle on-page toast shows which rules fired and
against which URL, so you always know what was intercepted.


โ”€โ”€ USE CASES โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€

โ€ข Mock API responses during frontend development
โ€ข Test error states (404, 500) without backend support
โ€ข Simulate slow network conditions
โ€ข Override feature flags or A/B test payloads
โ€ข Strip or inject authentication headers
โ€ข Redirect production API calls to a local dev server


No external servers. No data leaves your browser.
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Permissions and data

Required permissions:

  • Block content on any page
  • Access browser tabs
  • Access your data for all web sites

Optional permissions:

  • Access your data for all web sites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Version
1.0.0
Size
31.35 kB
Last updated
5 days ago (1 May 2026)
Related Categories
  • Web Development
Licence
MIT Licence
Version History
  • See all versions
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