[BUG] Slash command autocomplete doesn't work in the middle of text when vim mode is enabled

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?

When vim mode is enabled (/vim), typing "/" in the middle of text does not trigger slash command autocomplete.

According to the official documentation:

Added slash command autocomplete support when / appears anywhere in input, not just at the beginning

However, this only works when vim mode is disabled. In vim mode (insert mode), typing "/" mid-sentence does not show the autocomplete dropdown.

What Should Happen?

Slash command autocomplete should appear when typing "/" anywhere in the input, regardless of whether vim mode is enabled or not.

Error Messages/Logs

(No error messages - the autocomplete simply doesn't appear)

Steps to Reproduce

1. Enable vim mode by typing /vim and pressing Enter
2. Type some text, e.g., "Hello "
3. Type "/" to trigger slash command autocomplete
4. Notice: No autocomplete dropdown appears

To verify it's vim-mode specific:

1. Disable vim mode by typing /vim again
2. Type "Hello /"
3. Notice: Autocomplete dropdown now appears correctly

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.2 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

iTerm2

Additional Information

<img width="572" height="90" alt="Image" src="https://github.com/user-attachments/assets/8ed6ccc8-b337-4abf-8615-bace7b813034" />
<img width="403" height="89" alt="Image" src="https://github.com/user-attachments/assets/718f8af1-f497-4fac-8beb-1a197c9765ad" />