ask_user input drops keys when keypresses arrive with 0ms delay (kmonad/QMK home row mods)

[danila-xalgo-io]

Description

When using kmonad (or similar keyboard remapping tools like QMK) with home row mods, keys are dropped in the ask_user interactive prompt. This happens because these tools can send multiple key events with 0ms delay when "rolling" between keys.

Environment

• copilot-cli version: 0.0.398
• OS: macOS (Darwin)
• Terminal: Tested in Ghostty, WezTerm, with and without tmux
• Keyboard: kmonad with tap-hold-next-release home row mods

Root Cause Analysis

1. Node.js receives all keypress events correctly - verified with a raw keypress listener
2. Standalone Inquirer.js works perfectly - tested with @inquirer/prompts directly
3. Only copilot-cli's ask_user prompt drops keys

When rolling keys quickly (e.g., typing "aoeu" in Dvorak), kmonad sends adjacent keys with 0-2ms between them:

+  14ms  o
+   1ms  e    <-- 1ms after previous
+  92ms  u
+ 141ms  a
+  29ms  o
+   0ms  e    <-- 0ms (same millisecond!)
+  69ms  u

Reproduction Script

#!/bin/bash
# Save as rapid-key-inject.sh
echo "Waiting 2 seconds - focus the copilot ask_user prompt..."
sleep 2

osascript <<'APPLESCRIPT'
tell application "System Events"
    -- No delay between keystrokes (simulates kmonad rolling)
    keystroke "aoeu aoeu aoeu"
end tell
APPLESCRIPT

echo "Done."

Steps:

1. Start copilot: copilot
2. Trigger an ask_user prompt (e.g., ask copilot to do something that requires clarification)
3. Run ./rapid-key-inject.sh
4. Quickly focus the copilot ask_user input
5. Observe: characters are dropped

Expected: "aoeu aoeu aoeu" appears in the input
Actual: Some characters are missing (e.g., "aoe aoe aoe" or worse)

Additional Notes

• Typing with 1ms delay between keys works fine
• The prompt "blinks" when this happens, suggesting re-rendering interference
• Flags like --screen-reader, --stream off do not help
• This is likely a race condition in the render loop that drops keypresses

Workarounds Attempted (none worked)

• --screen-reader
• --stream off
• NODE_NO_READLINE=1
• Running through script -q /dev/null copilot
• Various kmonad tap-hold configurations

Suggested Fix

The ask_user input handler should queue all keypress events and process them sequentially, rather than potentially dropping events during re-renders.

[boytunp]

setting TERM=xterm-256color worked for me. Actually co-pilot came up with the solution.

[examon]

This has been fixed as of v1.0.15. The input component was refactored to eliminate the render race condition that caused keystroke loss during rapid typing. If you're still seeing dropped keys with kmonad or QMK home row mods, please feel free to reopen this issue.