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Preview of Open Headers

Open Headers by Bithub Team SRL

Open Source DevToolkit, inside a browser extension. Modify live browser requests. Manage API Collections. Team Collaboration.

5 (2 reviews)5 (2 reviews)
3 Users3 Users
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Extension Metadata

About this extension
Local-first: no account, no cloud, your data stays on your machine.

BROWSER INTERCEPTOR

• Eleven rule types, one condition language: rewrite headers, block, redirect, delay, mock responses, edit bodies and query strings, merge, inject CSS/JS, modify WebSocket and SSE messages
• Static rules compile into the browser's own network layer and catch every request: pages, frames, fetch, XHR, images, fonts, scripts
• No proxy port and no CA certificate: rules run with the page's own permissions, nothing man-in-the-middles your traffic
• DevTools-grade network panel with request and response inspection
• Five variable scopes in every rule: vault, environment, collection, workspace, live

API CLIENT

• HTTP, GraphQL with schema introspection, WebSocket, Socket.IO and SSE right in the browser; gRPC and MQTT through the desktop companion
• Collections with folders, environments, OAuth 2.0 with PKCE and refresh, multipart file uploads
• Pre- and post-response scripts and assertions
• Workflows: chain and schedule requests with dependencies, AND/OR run conditions and parallel steps; every response value lands in a live variable any rule can inject into real traffic
• Import from cURL, HAR, Postman, Insomnia and OpenAPI
• Encrypted vault for secrets and tokens, referenced by name, never exposed

TEAM COLLABORATION

• Multi-workspace: your personal workspace and the team's shared one side by side, each in its own tab
• Sync through back-ends you control: the desktop app, a box on your LAN, or a self-hosted server
• Self-hosted server with SSO, RBAC user management and audit logs
• Optional Git back-end for durable workspace history: a new device bootstraps from Git and auto-syncs from there
• Concurrent multi-user editing
• Work offline, auto-sync when back online

Our vision: a platform where everyone can use local tools to generate their own local data and own it, not a cloud vendor middleman.

Everything is free to use and free to self-host. Like it should be.
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Permissions and data

Required permissions:

  • Exchange messages with programs other than Firefox
  • Clear recent browsing history, cookies, and related data
  • Block content on any page
  • Read your browsing history
  • Extend developer tools to access your data in open tabs
  • Control browser proxy settings
  • Access browser tabs
  • Access browser activity during navigation
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.

Optional data collection, according to the developer:

  • Technical and interaction data
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More information
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Version
2026.9.1
Size
6.42 MB
Last updated
2 days ago (Sep 12, 2026)
Related Categories
  • Web Development
License
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