[BUG] Clickable file links in chat panel no longer open files in editor (regression in v2.1.178+)

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?

File links rendered as clickable blue underlined text in the Claude Code chat panel
no longer open the corresponding file in the VS Code editor when clicked.
This appears to be a regression introduced in a recent update (v2.1.178 or later).

What Should Happen?

The referenced file opens in the VS Code editor.

Error Messages/Logs

Nothing happens. The file does not open.

Steps to Reproduce

1. Open any workspace folder in VS Code with the Claude Code extension active
2. Start a new conversation in the Claude Code chat panel
3. Ask Claude to reference or list files in the workspace, for example:

> "List the markdown files in this project"

1. Claude responds with file references rendered as Markdown links,

e.g. [README.md](README.md) — displayed as blue underlined text in the chat

1. Click the blue underlined link
2. Nothing happens — the file does not open in the editor

Alternatively (minimal reproduction):
Ask Claude to perform any task that causes it to output a [label](filepath) style
file reference in its response, then click the rendered link.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.177

Claude Code Version

2.1.181 (regression likely introduced in 2.1.178)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

• The same file paths, when rendered as clickable links in the GitHub Copilot chat panel,

open correctly in the editor. This confirms the issue is specific to the Claude Code extension,
not a VS Code or filesystem problem.

• Multiple versions are installed locally (2.1.177, 2.1.178, 2.1.179, 2.1.181),

suggesting the regression was introduced between 2.1.177 and 2.1.178.

• Paths containing Japanese (multi-byte) characters are affected,

but the root cause is likely not encoding — Copilot handles the same paths without issue.