statusLine.command is not executed or rendered when footer.showCustom=true

[soydachi]

Describe the bug

With footer.showCustom=true and statusLine.command set to a valid executable, Copilot CLI 1.0.43 on macOS reads settings.json for built-in footer items, but never executes the custom status line command and never renders custom output.

There is no visible error in the TUI.

Affected version

GitHub Copilot CLI 1.0.43

Steps to reproduce

1. Put this in ~/.copilot/settings.json:

{
  "statusLine": {
    "type": "command",
    "command": "/bin/date",
    "padding": 1
  },
  "footer": {
    "showCustom": true,
    "showBranch": true,
    "showAgent": true
  }
}

2. Start a fresh copilot session in a new terminal.
3. Verify that built-in footer settings are applied (for example, showBranch affects the footer, which shows settings.json is being read).
4. Run /statusline and verify that custom is enabled.
5. Observe that the custom output never appears in the status line.

Additional verification

I also replaced /bin/date with a trivial local shell script that:

• writes a timestamp to a file
• reads stdin
• prints a short string to stdout

That script also never ran: no file was created and no custom output was rendered.

Expected behavior

When footer.showCustom=true, the configured statusLine.command should execute, receive the current session status JSON on stdin, and render its stdout in the custom status line area.

Actual behavior

Built-in footer/status line settings are applied, but the custom statusLine.command appears not to execute at all and nothing is rendered for the custom status line item.

Environment

• OS: macOS
• Copilot CLI: 1.0.43

[1021ky]

I also suspect this is a bug. I’m adding a few extra data points from my side in case they help narrow it down.

I can reproduce this consistently with an isolated COPILOT_HOME, so it does not seem to depend on my existing user config.

Minimal repro

1. Create an empty temp dir and use it as COPILOT_HOME
2. Put only this in settings.json:

{
  "statusLine": {
    "type": "command",
    "command": "/bin/date",
    "padding": 1
  },
  "footer": {
    "showCustom": true,
    "showBranch": true,
    "showAgent": true
  },
  "logLevel": "all"
}

3. Start a fresh copilot session
   Observed

• Built-in footer items are applied, so settings.json is definitely being read
• Custom output never appears
• No visible TUI error

4. I also tested with a local script instead of /bin/date:

 #!/usr/bin/env bash
 echo "$(date)" >> /tmp/copilot-statusline-ran.log
 printf "TEST-STATUSLINE\n"

Result

• TEST-STATUSLINE never appears
• /tmp/copilot-statusline-ran.log is never created
  So in my environment this looks like statusLine.command is not being executed at all, not just failing to render.

Environment

• Copilot CLI:
  1.0.43
• OS: macOS
  26.4.1 (25E253)
• Terminal: Ghostty
  1.3.1
• Install method: brew