Desktop app: Browser pane forgets its width when toggled off and back on

What happened

In the macOS desktop app, the Browser pane forgets the width I set. If I drag the divider to make the pane narrow, then hide the pane and show it again, it comes back at a much wider default instead of the width I left it at — squeezing the conversation column.

It happens every time, within a single session. No app restart is involved: hide, show, and the width is already gone.

Steps to reproduce

1. Open the Browser pane.
2. Drag the divider so the pane is noticeably narrower than the default (in my case about a third of the window).
3. Toggle the Browser pane off.
4. Toggle it back on.

Expected

The pane reopens at the width I last dragged it to.

Actual

It reopens at a wide default — roughly half the window — and the conversation reflows into a narrow column. The drag has to be redone every single time.

Notes

The width does not appear to be persisted anywhere on disk, which may be the root of it:

• ~/Library/Application Support/Claude-3p/ contains only claude_desktop_config.json (MCP config).
• defaults read com.anthropic.claudefordesktop has no pane, width, or split keys.
• ~/.claude/settings.json has no layout keys either.

So there is also no workaround available to users — the value can't be pinned in config, and there's no setting to change.

Related but not the same: #71752 is about the left sidebar failing to resize while dragging. Here the drag works fine; the width just isn't retained across a hide/show.

Environment

• Claude Code 2.1.220
• Claude desktop app 1.26832.0
• macOS 26.6.1 (Apple silicon)