Claudezilla

Claudezilla

Browser automation for Claude Code that runs on Firefox — for systems where Chrome is unavailable, unwelcome, or policy-prohibited.

[](./CHANGELOG.md)

The only Firefox-native MCP server for Claude Code. Navigate, automate, screenshot, and extract data on any system that runs Firefox — no Chrome dependency, no Google infrastructure.

Claudezilla.com

Why Claudezilla?

Anthropic's official browser tool requires Chrome. If you're on a system where Chrome is not available — or not acceptable — Claudezilla gives Claude Code the same browser automation capabilities through Firefox.

• Linux-native — Works with the Firefox that ships on Debian, Fedora, RHEL, Ubuntu, and every major distro. No Google repository required.
• Zero telemetry — All communication runs through a local Unix socket. No data leaves your machine. No Google account, no Chrome sync, no phone-home.
• Hardened environments — Built for Tails, Whonix, Qubes OS, air-gapped networks, and enterprise Linux where package policy prohibits Chrome.
• Multi-agent safe — 12-tab shared pool with 128-bit agent IDs, ownership tracking, and screenshot mutex. Multiple Claude sessions coexist safely.
• Full feature parity — Click, type, scroll, screenshot, evaluate JS, access DevTools console and network. Same capabilities, different browser.

Quick Start

1. Install the extension

Install from Firefox Add-ons

2. Install the native host

git clone https://github.com/boot-industries/claudezilla.git
cd claudezilla

# macOS
./install/install-macos.sh

# Linux
./install/install-linux.sh

The installer automatically:

• Installs the native messaging host
• Runs npm install for MCP dependencies
• Configures Claude Code MCP settings (~/.claude/mcp.json)

No manual config required — restart Claude Code and you're ready.

What Can Claude Do?

| Capability | Description | |------------|-------------| | Browse | Open URLs, navigate pages, manage tabs | | Read | Extract text, get page structure, accessibility tree | | Interact | Click buttons, fill forms, press keys, scroll | | Screenshot | Capture pages (JPEG, configurable quality) | | Consent | Auto-dismiss cookie/GDPR consent dialogs | | Wait | Handle SPAs and dynamic content | | Focus Loops | Persistent iterative tasks until completion |

Support Development

Claudezilla is free and open source. You can support its development with a one-time donation or monthly sponsorship:

• Click the ☕ Buy Me a Coffee button on the welcome page after first install
• Or use the ☕ Support this project link in the extension popup
• Donations are processed securely through Stripe

See [STRIPESETUP.md](./STRIPESETUP.md) for deployment and configuration details.

Example Usage

Once connected, Claude can use commands like:

Claude, open https://example.com and take a screenshot
Claude, fill in the search box with "Firefox automation" and click submit
Claude, get all the links on this page

Available Tools

Browser Control

• firefox_create_window — Open URL in browser
• firefox_navigate — Navigate current tab to a URL
• firefox_get_content — Read page text (50K char limit)
• firefox_click — Click element by CSS selector
• firefox_type — Type into input field
• firefox_press_key — Keyboard events (Enter, Tab, shortcuts)
• firefox_screenshot — Capture viewport (supports annotated mode)
• firefox_get_tabs / firefox_close_tab — Manage tabs
• firefox_list_all_tabs — List all open tabs, including ones not yet under Claudezilla's control
• firefox_attach_tab / firefox_detach_tab — Attach to (or release) a tab the user already has open, driving it in place instead of opening a new one

Configuration

• firefox_activate — Load tool categories on demand (lazy loading saves ~6K tokens)
• firefox_set_config — Set domain allowlist, consent auto-dismiss, and session config
• firefox_set_private_mode — Toggle private/regular browsing
• firefox_handle_consent — Dismiss cookie/GDPR consent dialogs

Focus Loops

• firefox_start_loop — Start persistent iteration with prompt and max iterations
• firefox_stop_loop — Stop active loop manually
• firefox_loop_status — Check iteration count and state

Page Analysis

• firefox_get_page_state — Structured data (headings, links, buttons, diff support)
• firefox_get_accessibility_snapshot — Semantic tree (screen reader view)
• firefox_get_element_info — Element attributes and styles
• firefox_wait_for — Wait for element, text, or URL pattern
• firefox_scroll — Scroll to element or position

Diagnostics

• firefox_diagnose — Check connection health, socket status, and troubleshoot issues

Requirements

• Firefox 91+
• Node.js 18+
• Claude Code CLI

Privacy & Security

Claudezilla is designed with security in mind:

• Command whitelist — Only predefined actions allowed
• Local only — Communication via Unix socket (no network exposure)
• Tab isolation — Each Claude session owns its tabs
• URL validation — Blocks dangerous schemes (javascript:, data:)
• Supply chain hardened — ignore-scripts=true, pinned dependencies, pnpm strict isolation, SHA-pinned CI actions, timing-safe auth

Works in both regular and private Firefox windows. Tab navigation respects ownership — Claude can only navigate tabs it created.

See [SECURITY.md](./SECURITY.md) for the full security model.

Architecture

Claude Code ←→ MCP Server ←→ Unix Socket ←→ Native Host ←→ Firefox Extension

The extension uses Firefox's Native Messaging to communicate with a local Node.js process, which exposes tools via the Model Context Protocol.

Contributing

Issues and PRs welcome. See [CLAUDE.md](./CLAUDE.md) for development notes.

License

MIT

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Author: Chris Lyons — boot.industries

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: boot-industries
• Source: boot-industries/claudezilla
• License: MIT
• Homepage: https://boot.industries

Install and usage instructions live in the source repository linked above.