Codex exit leaks Ctrl+Tab CSI-u input into a Herdr pane

[ucalyptus]

Is this a reproducible bug?

• I confirm this is a reproducible bug, not a feature request, idea, question, contribution proposal, or direction check.
• I reproduced this bug on the version and environment reported below using the exact steps provided.

Current behavior

After exiting codex in a Herdr pane, pressing Ctrl+Tab at the returned zsh prompt prints the raw fragment 9;5:1u. The same Codex exit in a normal zsh terminal does not leave this fragment.

Expected behavior

Exiting Codex should restore normal keyboard handling in the Herdr pane. Ctrl+Tab should not be delivered to zsh as a raw escape sequence.

Reproduction

1. Start Herdr and open a zsh pane.
2. Run codex.
3. Exit Codex.
4. Press Ctrl+Tab at the pane zsh prompt.
5. Observe 9;5:1u rendered as text.

Impact

A normal keyboard shortcut becomes literal input after each Codex session, so the pane must be manually reset before continuing shell work.

Environment

• Herdr version: 0.7.5
• Update channel: stable
• Operating system: macOS 26.5.2 (25F84)
• Terminal: Herdr local pane
• Shell, if relevant: zsh
• Relevant config, if any: default Herdr config (only onboarding = false)

[akbash-bot]

Closing as an exact duplicate of #2293, which has the same reproduction and environment. If a concrete detail differs from that report and changes the classification, please reply and tag a maintainer.

[ogulcancelik]

@akbash-bot it's not a duplicate

[akbash-bot]

Reopened. #2293 was closed by automated intake and is not the canonical tracking issue, so treating this report on its merits.

[ucalyptus]

yup @ogulcancelik , I see this

[akbash-bot]

Thanks — I can reproduce raw Ctrl+Tab input on Linux, but it is already present before Codex there and uses a different protocol, so I need one macOS state comparison to isolate the reported transition.

Could you run this once in a fresh Herdr zsh pane, then again immediately after exiting Codex the same way?

(sleep 0.2; printf '\033[?u' > /dev/tty) & cat -v

Each run should print one short line like ^[[?0u; press Ctrl+C after that line appears. Please paste only the before/after lines and say how you exited Codex (for example, Ctrl+C or Ctrl+D). This command only queries the pane keyboard-protocol flags and does not read terminal content.

[ucalyptus]

same issue

[ucalyptus]

Thanks — I can reproduce raw Ctrl+Tab input on Linux, but it is already present before Codex there and uses a different protocol, so I need one macOS state comparison to isolate the reported transition.

Could you run this once in a fresh Herdr zsh pane, then again immediately after exiting Codex the same way?

(sleep 0.2; printf '\033[?u' > /dev/tty) & cat -v
Each run should print one short line like ^[[?0u; press Ctrl+C after that line appears. Please paste only the before/after lines and say how you exited Codex (for example, Ctrl+C or Ctrl+D). This command only queries the pane keyboard-protocol flags and does not read terminal content.

ucalyptus@Sayantans-MacBook-Pro ~/mychoice  $ (sleep 0.2; printf '\033[?u' > /dev/tty) & cat -v
[1] 57539
[1]  + done       ( sleep 0.2; printf '\033[?u' > /dev/tty; )
^[[?0u

[akbash-bot]

Thanks — the ^[[?0u line is useful, but I cannot tell whether it was captured before or after Codex. Please reply in exactly this form:

before: ^[[?...u
after: ^[[?...u
exit: Ctrl+C / Ctrl+D / other

If the posted ^[[?0u was the after value, you only need to run the same command once in a fresh pane for the before value. This distinguishes stale pane protocol state from raw host input passthrough.