Ctrl-G editor (vim) drops ~50% of keystrokes in INSERT mode

[ccapon]

Describe the bug

Symptoms:

• Pressing Ctrl-G to edit prompt in $EDITOR (vim) opens the editor correctly
• In INSERT mode, roughly every other keystroke is silently dropped (e.g. typing abcdefghi produces abdegi)

Affected version

OS: Linux (Ubuntu), lxterminal + tmux, TERM=xterm-256color
GitHub Copilot CLI 1.0.49

Steps to reproduce the behavior

See bug description

Expected behavior

The TUI should suspend its PTY hooks (or fully hand off the terminal) while the child editor process is running, then reclaim it on exit.

Additional context

WORKAROUND
Launch vim in a new tmux window (separate PTY):

$EDITOR wrapper (~/.local/bin/vim-copilot)

tmux new-window "/usr/bin/vim '$1'; tmux wait-for -S vim-done"
tmux wait-for vim-done

[linus-entiros]

This happens for me too using NeoVim with alacritty on NixOS

[VD-Techlead]

We are seeing this on windows WSL using VI as well

[caspian-ireland]

Thanks for raising - having the same issue here.

GitHub Copilot 1.0.49
macOS 26.5, arm64
$EDITOR set to vim

Likely duplicate of #3384

[jt-mckesson]

I am having this issue with Vim inside Copilot CLI on the latest update today as well. It was working fine before updating to 1.0.49.

Copilot CLI 1.0.49
macOS 26.5
Apple M3 Max

[examon]

This looks like a duplicate of #3384, which tracks the same v1.0.49 Ctrl+G external-editor input issue where keystrokes can be dropped while the editor is open. That issue has been addressed. If you believe this is a separate issue, please comment with details and we'll take another look.

[ccapon]

This looks like a duplicate of #3384, which tracks the same v1.0.49 Ctrl+G external-editor input issue where keystrokes can be dropped while the editor is open. That issue has been addressed. If you believe this is a separate issue, please comment with details and we'll take another look.

@examon good catch sorry I did not see it before.