t3code-rtl

Persian and Arabic right-to-left support for T3 Code chat messages.

t3code-rtl patches T3 Code locally. Persian and Arabic message blocks become RTL and use the bundled Arad font; code blocks, terminals, diffs, the composer, and the sidebar remain LTR.

What it changes — and what it does not

Only paragraphs inside chat messages that contain Persian or Arabic text are affected. Nothing else in T3 Code is changed.

• A paragraph, list item, heading, or table cell inside a chat message gets dir="rtl" and the Arad font only if it contains at least one Persian or Arabic character.
• Every block without such text is left exactly as it was — same direction, same font, same styling.
• Code blocks, inline code, diffs, and terminal output are never flipped, even when they appear inside an RTL paragraph.
• The composer, sidebar, menus, settings, and the rest of the interface are never touched.

The patch is a single small script injected into the app's index.html. It does not change any application logic, settings, data, or network behavior.

[!WARNING] This unofficial tool modifies files inside the T3 Code application bundle. Reapply the patch after every T3 Code update.

Requirements

Node.js 20 or later, plus one of these T3 Code installations:

• macOS desktop app: any T3 Code*.app in /Applications. The managed update mode additionally requires the Homebrew cask t3-code.
• Linux desktop app: /opt/t3code-bin or /opt/t3code-nightly-bin (AUR packages).
• t3 npm package (npm install -g t3, the same server that npx t3 runs): detected automatically through npm root -g.
• Windows desktop app: %LOCALAPPDATA%\Programs\T3 Code (winget). Untested; report problems in the issue tracker.

Other locations can be supplied with T3CODE_APP_DIRS (one app or package directory per line).

npx t3@latest downloads a fresh copy into the npx cache on every run, so a patch applied there does not persist. Use npm install -g t3 and run t3 instead.

Run

npx t3code-rtl

The first run detects T3 Code, asks how updates should work, applies the patch, and remembers the choice. Restart T3 Code afterwards. It has two update modes only:

• Managed (macOS, recommended): disables T3 Code's internal updater for this tool and uses t3code-rtl update to upgrade via Homebrew and reapply the patch. Only offered when T3 Code was installed with Homebrew.
• Native: leaves T3 Code automatic updates enabled. After an update, run npx t3code-rtl patch and restart the app.

No background watcher is installed.

Commands

npx t3code-rtl                 # interactive menu
npx t3code-rtl setup           # choose update strategy and patch
npx t3code-rtl patch           # apply the patch
npx t3code-rtl unpatch         # remove the patch, LaunchAgent, and settings
npx t3code-rtl status          # show detected apps, patch state, and update mode
npx t3code-rtl doctor          # show detailed diagnostics
npx t3code-rtl update          # Homebrew update + patch on macOS

To install a permanent command instead:

npm install -g t3code-rtl
t3code-rtl

Troubleshooting

Run npx t3code-rtl status to see whether each detected app is currently patched. After a T3 Code update the state returns to not patched; run patch again.

npx t3code-rtl doctor prints the platform, config path, Homebrew and LaunchAgent state, and the bundle layout and ASAR integrity setting for each app.

"ASAR integrity validation is enabled; refusing to patch" — the installed T3 Code build verifies its app.asar and would refuse to start after modification. The tool stops rather than break the app. If you want to try anyway, run with T3CODE_RTL_FORCE=1; reinstall T3 Code if it no longer starts.

Testing without touching the desktop app

The t3 npm package serves the same web client as the desktop app, so it is a safe way to try the patch:

mkdir t3-sandbox && cd t3-sandbox && npm install t3@latest
T3CODE_APP_DIRS="$PWD/node_modules/t3" npx t3code-rtl patch
npx t3 start --port 4711 --base-dir "$PWD/data"

Open the printed URL and send a Persian or Arabic message. npx t3code-rtl unpatch with the same T3CODE_APP_DIRS reverts it; delete the sandbox directory when done.

Contributors can run the automated version of this, which cleans up after itself: npm run test:smoke (fake bundles) or SMOKE_T3=1 npm run test:smoke (also the real t3 package).

Safety

The patch is idempotent: each application replaces the prior injected block. Current ASAR layouts are changed in place and receive an unpacked index.html override. unpatch removes the injected block and the LaunchAgent; reinstall T3 Code through its package manager to restore the original bundle byte for byte.

License

The code is MIT licensed. The bundled Arad font is available under the SIL Open Font License 1.1.