Windows Codex App project action leaves PowerShell at continuation prompt after command completes

Summary

On Windows, running a minimal Codex App project action can leave the integrated PowerShell terminal at the >> continuation prompt after the action command has already completed successfully.

The command output appears, the normal PS ...> prompt appears, and then the terminal enters a new >> continuation prompt. This suggests an extra trailing newline, unbalanced input fragment, or terminal/action injection artifact after the action completes.

Environment

• App: Codex desktop app on Windows
• Codex App version: not captured from About Codex in this repro; can be updated if needed
• OS: Windows 10 Pro 25H2, build 26200.8328
• Windows PowerShell: 5.1.26100.8328
• PowerShell 7: 7.6.1 tested manually inside the Codex App terminal
• Integrated terminal shell primarily tested: PowerShell
• Related setting also tested: Command Prompt was tried for the separate paste issue, but this issue concerns PowerShell continuation prompt behavior after project actions

Minimal project action

Using a project .codex/environments/environment.toml with a minimal action like:

[[actions]]
name = "Run"
icon = "run"
command = "Write-Host noop-ok"

Steps to reproduce

1. Open Codex App on Windows.
2. Use a project with the minimal action shown above.
3. Set Integrated Terminal Shell to PowerShell.
4. Open the project/session so the action is visible.
5. Click the project action.
6. Observe the integrated terminal command and output.

Observed terminal shape:

Set-Location -LiteralPath '<project path>'; Write-Host noop-ok
noop-ok
PS <project path>>
>>

The important part is that noop-ok is printed and the command has completed, but the terminal then enters the PowerShell continuation prompt (>>).

Expected behavior

After a project action completes successfully, the integrated terminal should return to a normal prompt and remain ready for the next command, for example:

PS <project path>>

Actual behavior

After the action completes, the terminal ends up at:

>>

The user has to cancel the continuation state manually, for example with Ctrl+C, before continuing normally.

Additional checks performed

• A hand-typed Write-Host enter-test in the same terminal executes normally and does not enter >>.
• Changing the action command to cmd /c echo noop-ok did not resolve the behavior in this environment.
• Entering PowerShell 7.6.1 (pwsh) and clicking the project action also did not resolve the behavior.
• This was observed separately from a paste duplication issue in the same Codex App integrated terminal. The action continuation prompt behavior appears related to the action injection path rather than the shell command itself.

Impact

This is less severe than the paste duplication issue, but it makes project actions feel unreliable on Windows because a successful action can leave the integrated terminal in a continuation state. It is easy to recover with Ctrl+C, but it is surprising and can confuse subsequent terminal input.