RTL (Hebrew/Arabic) text rendering broken on Linux terminals (COSMIC Terminal, GNOME Terminal)

Description

RTL (Right-to-Left) text for Hebrew, Arabic, and Persian is not rendering correctly in Claude Code on Linux terminals.

Version 2.1.74 (March 12, 2026) fixed RTL rendering for Windows Terminal, conhost, and VS Code integrated terminal, but Linux terminal emulators were not included in this fix.

Environment

• Claude Code version: 2.1.74
• OS: Pop!_OS 24.04 LTS (Ubuntu-based)
• Kernel: Linux 6.18.7
• Desktop: COSMIC Desktop 1.0
• Terminal: COSMIC Terminal 1.0.8
• Locale: en_US.UTF-8
• Shell: zsh

Current behavior

Hebrew text in Claude Code output appears garbled/reversed/misaligned in Linux terminal emulators. The BiDi (bidirectional) text algorithm does not properly handle RTL script mixed with LTR content (code, file paths, numbers).

Expected behavior

Hebrew/Arabic/Persian text should render correctly in RTL direction, matching the fix already applied for Windows terminals in v2.1.74.

Affected terminals (Linux)

• COSMIC Terminal (Pop!_OS default)
• GNOME Terminal
• Likely affects all Linux terminal emulators (kitty, Alacritty, WezTerm, etc.)

Related issues

• #11050 — RTL support request (closed as not planned)
• #30100 — RTL text rendering broken in VS Code extension (open)
• #12635 — RTL support for Persian (open)
• #16814 — RTL support in Claude Desktop (open)

Notes

The v2.1.74 changelog explicitly mentions "Windows Terminal, conhost, and VS Code integrated terminal" — Linux terminals appear to have been overlooked. Since the fix already exists for Windows, extending it to Linux should be feasible.

Many Hebrew and Arabic-speaking developers use Linux as their primary development environment.