[BUG] Keybinding null binding for alt+left is applied inconsistently — key slips through after 2-3 presses

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Setting alt+left to null in keybindings.json to disable Option+Left does not
hold consistently. It works for the first 1-2 presses, but on the 3rd or 4th press
the key slips through and wipes text in the input box.

keybindings.json
{
"bindings": [
{
"context": "Chat",
"bindings": {
"alt+left": null
}
}
]
}

What Should Happen?

Expected behavior
Option+Left is always a no-op — never reaches the terminal or modifies input.

Actual behavior
Option+Left is intercepted for the first 1-2 presses, then slips through
and the terminal's default escape sequence behavior wipes input text.

Error Messages/Logs

N/A

Steps to Reproduce

1. Add the above keybinding to ~/.claude/keybindings.json
2. Open Claude Code and type some text in the chat input
3. Press Option+Left repeatedly (3-4 times)
4. On the 3rd or 4th press, the key is not intercepted and text is wiped

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.105

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

iTerm2

Additional Information

_No response_