Statusline command output not rendered in TUI (Windows 11 + WezTerm, v2.1.143)

Summary

statusLine is configured in settings.json and the configured command is invoked by Claude Code (verified via a debug log written from the script), but its stdout is never rendered anywhere in the TUI. Even a minimal script that prints a fixed ASCII string produces no visible output.

Environment

• OS: Windows 11 Home 10.0.26200
• Terminal: WezTerm 20260117-154428-05343b38
• Claude Code: 2.1.143 (npm global install)
• Shell launched by statusLine: pwsh 7.6.1 (also observed: powershell 5.1.26100.8457 — Claude Code appears to invoke both)

Configuration (~/.claude/settings.json)

{
  "permissions": { "defaultMode": "auto" },
  "statusLine": {
    "type": "command",
    "command": "pwsh -NoProfile -NonInteractive -File C:\Users\81809\.claude\statusline.ps1"
  }
}

Reproduction

1. Replace statusline.ps1 with a minimal script:

``powershell
$null = $input | Out-String
Add-Content -Path "$HOME\.claude\statusline_debug.log" -Value "called"
Write-Output "STATUS LINE TEST OK"
``

1. Restart Claude Code in WezTerm.
2. Observe: statusline_debug.log grows (script is invoked) but STATUS LINE TEST OK is never displayed in the UI.

Evidence the script runs

[2026-05-19 09:09:22] CALLED stdin_len=218 ps=7.6.1
[2026-05-19 09:09:44] CALLED stdin_len=222 ps=7.6.1
[2026-05-19 09:15:00] MINIMAL called from PS 7.6.1
[2026-05-19 09:15:00] MINIMAL called from PS 5.1.26100.8457

Expected

STATUS LINE TEST OK appears in the statusline region of the TUI.

Actual

The statusline region is blank/absent. Screenshots taken at known-idle states (after Cogitated for Nm Ns past-tense indicator appears) show no statusline output above or below the input prompt.

Tried (no effect)

• Restarting Claude Code in a fresh WezTerm pane
• Adding "padding": 1 and "refreshInterval": 5 to the statusLine config
• Verifying the schema in claude-code-settings.schema.json matches our config
• Confirming script output is plain ASCII (so it can't be a font/encoding issue)