Codex CLI crashes on Option+Backspace after dragging in image

What version of Codex is running?

codex-cli 0.38.0

Which model were you using?

gpt-5-codex

What platform is your computer?

Darwin 25.0.0 arm64 arm

What steps can reproduce the bug?

1. Open codex in the terminal
2. Drag & drop a screenshot from Finder into the Codex CLI window.

• The editor inserts the absolute file path to the image.
• Example that triggered the crash on my machine:

``
/var/folders/0b/d70y9vxn7h938lyn98gwfq6r0000gn/T/TemporaryItems/NSIRD_screencaptureui_Xpmifz/Screenshot 2025-09-18 at 11.14.14 PM.png
``

1. With the cursor at the end of the inserted path, press Option+Backspace (⌥⌫) to delete the previous “word”.
2. The application panics and exits.

What is the expected behavior?

Option+Backspace should delete the previous word (or chunk) in the text area without crashing

What do you see instead?

Immediate crash with an assertion failure.

Additional information

The application panicked (crashed).
Message: assertion failed: self.is_char_boundary(n)
Location: tui/src/bottom_pane/textarea.rs:97

Backtrace omitted. Run with RUST_BACKTRACE=1 environment variable to display it.
Run with RUST_BACKTRACE=full to include source snippets.