Claude Code Desktop app (Windows, RTL locale): browser/preview pane renders a duplicate ghost layer over the Claude Code session

Summary

This is about the Claude Code Desktop app for Windows (the MSIX app hosting Claude Code sessions). On Windows with a Hebrew (RTL) display language, the embedded browser/preview pane of a Claude Code session draws a duplicate "ghost" copy of its content floating over the chat transcript.

Refiling #79038, which was auto-closed by triage as "not about Claude Code" -- it describes the Claude Code Desktop app itself.

Environment

• Claude (Desktop) 1.22209.3.0 through 1.30096.5.0 (MSIX, Microsoft Store) -- reproduced across all of them
• Windows 11 Pro, build 26200
• Windows display language: Hebrew (the app window is RTL-mirrored: window controls on the left)

Steps to reproduce

1. Set the Windows display language to Hebrew (or Arabic) so the app window is RTL-mirrored.
2. Launch the app (clean start, no DevTools, no scripts).
3. Open a Claude Code session and open the built-in browser/preview pane (e.g. have Claude preview an HTML file or start a dev server).

What happens

A duplicate copy of the pane's content floats over the chat area:

• disappears when the pane has focus, returns when focus moves back to the chat;
• persists with a single tab, across restarts;
• consistent with the live WebContentsView and its snapshot/placeholder layer being positioned in different coordinate spaces (one mirrored, one not).

Workaround

Launching with LTR chrome eliminates it entirely:

Claude.exe --lang=en-US --force-ui-direction=ltr

Related context

Hebrew-speaking Claude Code users currently need both this workaround and DevTools-injected CSS for readable RTL sessions (https://github.com/Sabarhealth/claude-rtl-companion). Native RTL support in the desktop app would make all of it unnecessary. Happy to provide screenshots, diagnostics, or test on preview builds.

🤖 Generated with Claude Code on the user's behalf