# Header request Injector

> Intercept HTTP/HTTPS requests and inject custom headers based on configurable URL filters.

Canonical page: [https://chrome-stats.com/d/header-request-injector](https://chrome-stats.com/d/header-request-injector)

## Overview

- **ID:** `header-request-injector`
- **Platform:** Firefox
- **Type:** Firefox add-on
- **Status:** Available
- **Publisher:** JedGBC
- **Category:** web-development
- **Daily users:** 3
- **Weekly downloads:** 1
- **Version:** 1.3.0
- **Last updated:** 2026-08-04
- **First published:** 2026-07-15
- **Size:** 82 KB
- **Data as of:** 2026-09-05
- **Store listing:** [Firefox Add-ons Store](https://addons.mozilla.org/firefox/addon/header-request-injector/)

## Description

The extension allows the user to define rules for modifying HTTP/HTTPS headers (adding, editing, or removing headers) that are automatically applied to network requests matching user-configured URL filters, while displaying the currently active rules in the popup.

Built for developers who need to simulate API clients, test gateway rules, or validate backend behavior with specific headers.

Key features:
<ul><li>URL filter matching with AND / OR logic</li><li>Optional URL exclude rules</li><li>Custom request headers per configuration</li><li>Global ON/OFF toggle</li><li>Recent match log (method, URL, timestamp, injected headers)</li><li>DevTools helper for quick inspection, commands on console:</li><li>HeaderInjector()</li><li>HeaderInjector('config')</li><li>HeaderInjector('log')</li><li>HeaderInjector.clear / HeaderInjector('log').clear / HeaderInjector('config').clear</li><li>Local storage only (no remote sync or external servers)</li></ul>
How it works:
<ul><li>You configure filters and headers in the popup</li><li>The extension applies rules in the browser</li><li>Matching requests are logged for debugging</li></ul>
Privacy:
<ul><li>Data is stored locally in your browser storage</li><li>No analytics, no telemetry, no external data collection</li></ul>
Intended use:
<ul><li>Development, QA, staging, and local debugging environments</li></ul>

## Rankings

- #57,518 — Overall
- #53 — inject
- #62 — request
- #134 — gateway
- #186 — header

## Permissions and access

### Permissions

- `declarativeNetRequest`
- `storage`
- `webRequest`
- `webRequestBlocking`
- `<all_urls>`

### Content script matches

- `<all_urls>`

## Safety

- **Risk impact:** High risk impact
- **Risk likelihood:** High risk likelihood

### Analysis details

- Allows access to all websites, posing a significant security risk as it can monitor and modify data from any visited site.
- This extension has low user count. Unpopular extensions may not be stable or safe.

> Some risk analysis details are omitted from this free response. [Upgrade to view the full analysis](https://chrome-stats.com/pricing).

## Similar extensions and apps

- [HTTP Header Plugin](https://chrome-stats.com/d/http-header-plugin) — 6 users
- [HeaderMod](https://chrome-stats.com/d/headermod) — 303 users
- [HeaderTools - Inject and Edit Request Headers](https://chrome-stats.com/d/headertools) — 108 users
- [Custom Header Injector](https://chrome-stats.com/d/custom-header-injector) — 1 users
- [Request Interceptor](https://chrome-stats.com/d/request_interceptor) — 408 users, 5.00 / 5
- [Header Editor](https://chrome-stats.com/d/simple-header-editor) — 5 users
- [Custom Header Tailor](https://chrome-stats.com/d/mozlla-custom-headers) — 1 users
- [Overhead — HTTP Header Editor](https://chrome-stats.com/d/overhead-http-header-editor) — 2 users, 5.00 / 5
- [Request Interceptor](https://chrome-stats.com/d/request-interceptor) — 580 users, 3.92 / 5
- [Header Modifier](https://chrome-stats.com/d/header-modifier) — 1 users
- [Modify HTTP Headers](https://chrome-stats.com/d/modify-http-headers) — 50 users, 5.00 / 5
- [HeaderForge](https://chrome-stats.com/d/headerforge) — 7 users

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Source: [Chrome-Stats](https://chrome-stats.com/d/header-request-injector)