Claude Desktop RTL Patch for macOS

Adds automatic right-to-left (RTL) text support to Claude Desktop on macOS. Hebrew and Arabic text is detected in real-time and aligned properly — both in the chat input and in Claude's responses — while code blocks stay left-to-right.

Based on claude-desktop-rtl-patch by @shraga100, which provides the same functionality for Windows. The RTL detection JavaScript is from that project; this repository adapts the patching mechanism for macOS (different app structure, Electron fuses, code signing).

What it does

• Chat input: automatically switches to RTL alignment when you type Hebrew/Arabic
• Claude's responses: detects RTL text in real-time as responses stream in
• Code blocks: always stay LTR — code formatting is never affected
• Mixed content: smart 3-layer detection handles sentences mixing Hebrew/Arabic and English
• Non-destructive: creates a patched copy of Claude.app — the original is never modified
• Distinct icon: the patched app has an "RTL" badge on its icon so you can tell them apart at a glance

Before & After

Requirements

• macOS (tested on macOS 15 Sequoia / macOS 26 Tahoe)
• Claude Desktop installed at /Applications/Claude.app
• Node.js (v16+) — needed for npx which runs @electron/asar and @electron/fuses
  • Install via nodejs.org or brew install node

Quick Start

# Clone the repo
git clone https://github.com/soguy/claude-desktop-rtl-mac.git
cd claude-desktop-rtl-mac

# Install the patch
./patch.sh --install

Downloaded the ZIP instead of cloning? You may need to make the script executable first: chmod +x patch.sh

That's it. A patched copy is created at ~/Applications/Claude-RTL.app (your home folder, not /Applications/) and launches automatically.

Usage

# Install (or update after Claude updates)
./patch.sh --install

# Remove the patched copy
./patch.sh --uninstall

# Check status
./patch.sh --status

# Interactive menu
./patch.sh

# Show help
./patch.sh --help

How it works

The patcher performs these steps:

1. Copies /Applications/Claude.app → ~/Applications/Claude-RTL.app
2. Extracts the Electron app.asar archive
3. Prepends the RTL detection JavaScript into .vite/build/*.js renderer files
4. Repacks the app.asar archive
5. Disables the EnableEmbeddedAsarIntegrityValidation Electron fuse — this is required because the modified archive has a different hash, and Electron would crash on startup without this step
6. Re-signs the app with an ad-hoc code signature

The original /Applications/Claude.app is never touched.

Why a copy instead of patching in-place?

Unlike the Windows version which patches the original installation directly, the macOS version creates a separate copy. This is safer because:

• No sudo required — ~/Applications/ is user-writable, so the script never needs elevated privileges
• Original stays intact — /Applications/Claude.app is never touched; you can always fall back to it
• Auto-updates keep working — Anthropic's updates go to the original app and won't conflict with the patch
• No risk of breaking Claude — if anything goes wrong, just delete the patched copy and the original is still there
• macOS protections respected — /Applications/Claude.app is owned by root and protected by App Management permissions; modifying it would require sudo and bypassing macOS security features

After Claude updates

When Claude Desktop auto-updates, it updates the original at /Applications/Claude.app. Your patched copy at ~/Applications/Claude-RTL.app is a separate, independent app — it won't receive auto-updates. After Claude updates, re-run the patcher to create a fresh patched copy from the new version:

./patch.sh --install

This creates a fresh patched copy from the updated original.

Tip: Keep the original Claude.app around for updates. Let it update itself normally, then re-run the patcher. The patched copy may show update prompts, but updates won't apply correctly to it — always update via the original app.

Uninstalling

./patch.sh --uninstall

This removes ~/Applications/Claude-RTL.app. The original Claude.app is unaffected.

Troubleshooting

"Claude quit unexpectedly" on launch

The ASAR integrity fuse was not properly disabled. Re-run ./patch.sh --install — it handles this automatically. If the problem persists, check that npx works: npx --yes @electron/fuses --help.

"Neither asar nor npx found"

Install Node.js: brew install node or download from nodejs.org.

The patch doesn't seem to work (no RTL alignment)

• Make sure you're running Claude-RTL.app from ~/Applications/, not the original Claude.app
• The RTL detection activates when you type Hebrew/Arabic characters — try typing שלום עולם
• Check Console.app for [Claude RTL] log messages

Keychain prompt: "Claude wants to use your confidential information"

On first launch, macOS will show a dialog asking for your password to allow access to "Claude Safe Storage" in your keychain. This is safe to approve. Claude Desktop uses Electron's safeStorage API to encrypt local data (like your login session). Since the patched copy has a different code signature than the original, macOS asks you to re-authorize access. This is a one-time prompt — macOS remembers the approval for future launches.

macOS Gatekeeper warning

Since the app is ad-hoc signed (not signed by Anthropic), macOS may show a warning on first launch. Right-click → Open to bypass it, or go to System Settings → Privacy & Security → Open Anyway.

App icon

The patched Claude-RTL.app has a custom icon with a visible "RTL" badge in the bottom-right corner, making it easy to distinguish from the original Claude.app in the Dock and Finder. The badge uses a white background with a dark border, so it's visible on both light and dark wallpapers/themes.

Project structure

claude-desktop-rtl-mac/
├── patch.sh          # Main patcher script
├── rtl-payload.js    # RTL detection JS (injected into Claude)
├── icon.icns         # RTL-badged app icon
├── README.md
└── LICENSE

Credits

• RTL detection logic: @shraga100 — claude-desktop-rtl-patch
• macOS adaptation: this project

License

MIT — see LICENSE.

The RTL detection JavaScript (rtl-payload.js) is from claude-desktop-rtl-patch, which is also MIT licensed.