[BUG] Left sidebar disappears / overlays content area on Windows desktop app

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

The left sidebar (the panel that lists Pinned and Recent sessions) intermittently breaks on the Claude Code Windows desktop app.

Two failure modes observed:

1. The sidebar disappears completely — the chat content shifts to fill the whole window, but there is no visible way to reopen the sidebar except by toggling it from the top-left icon (sometimes that does not bring it back either).
2. The sidebar enters a floating / overlay state where it visually overlaps the chat content instead of being docked. The main content renders flush against the left edge of the window, partially hidden behind the floating panel. This is what is captured in the attached screenshot.

This is a recurring issue — it has happened multiple times across sessions, including right now while writing this report.

What Should Happen?

The left sidebar should remain stably docked on the left side of the window, with the main chat content rendered to the right of it. Toggling it via the sidebar icon should reliably show/hide it without leaving it in a broken floating/overlay state.

Error Messages/Logs

Steps to Reproduce

1. Open the Claude Code desktop app on Windows 11.
2. Use the app normally across one or more sessions (open chats, switch sessions, send messages).
3. At some point (not deterministic, happens after a while of normal use, possibly after switching sessions or after the window has been resized/restored), the left sidebar either disappears entirely or enters a floating overlay state where it covers the leftmost portion of the chat content.
4. The main chat content area renders flush against the left edge of the window instead of being offset to the right of the sidebar.

Workarounds tried: toggling the sidebar via the top-left icon sometimes restores it (sometimes not); restarting the app restores it temporarily but the bug recurs.

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.68 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Environment notes: this is the Claude Code desktop app on Windows 11 Pro (build 10.0.22631), not the CLI in a terminal. The version reported above is what claude --version returns from the embedded terminal inside the app.

I have a screenshot of the failure mode (sidebar overlapping the chat content) and can attach it to this issue. Happy to upload on request or paste it directly into a comment.