[BUG] Claude VS extension No ide_selection context but existent selected file/line

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?

After the VS Code extension auto-updated to v2.1.278, get_current_selection stops returning any editor context. The active file path never appears in the prompt box, and selecting text never shows the ⧉ Selected N lines indicator. This happens in every workspace/project, not just one repo. It was working correctly before the update.

What Should Happen?

Description

After the VS Code extension auto-updated to v2.1.278, get_current_selection stops returning any editor context. The active file path never appears in the prompt box, and selecting text never shows the ⧉ Selected N lines indicator. This happens in every workspace/project, not just one repo. It was working correctly before the update.

Environment

• Claude Code VS Code extension: v2.1.278 (installed 2026-09-21, published 2026-09-19)
• VS Code: 1.138.0 (Electron 42.10.0)
• OS: macOS (Darwin arm64 25.6.0)
• Workspace: fully local (no SSH/WSL/Dev Container/Codespaces)
• "Attach Open File" setting: enabled

Steps to reproduce

1. Open any project in VS Code with the Claude Code extension installed.
2. Open a file and place the cursor in it, or select some text.
3. Open/focus the Claude Code panel and send a message.

Expected behavior

• The active file path shows in the prompt box.
• Selecting text shows ⧉ Selected N lines from <file> in the transcript.

Actual behavior

• No file path is ever shown, with or without a text selection.
• The extension log (Claude VSCode.log) shows the webview sending a get_current_selection request on session init (confirming the webview↔extension-host request path fires normally), but no active file/selection context is ever attached to messages.
• Option+K (insert file/line mention) does not open the file-mention picker either — it's intercepted by macOS as the dead-key composition for "˚" instead, suggesting the extension isn't registering/handling the keybinding or editor focus context correctly post-update.

Troubleshooting already tried (no effect)

• Reloaded the VS Code window (Developer: Reload Window)
• Confirmed "Attach Open File" setting is enabled
• Checked extension Output panel — no errors logged
• Confirmed VS Code (1.138.0) and extension (2.1.278) versions are both above the documented minimums (1.94.0 / 2.1.271)
• Checked ~/.claude/settings.json, ~/.claude/settings.local.json, and VS Code settings.json for permission deny rules or overrides — none found
• Reproduces in every project, not workspace-specific

Additional notes

The extension folder timestamp (~/.vscode/extensions/anthropic.claude-code-2.1.278-darwin-arm64) shows the auto-update landed the same day this regression appeared, strongly suggesting it's tied to the v2.1.278 release specifically.

Error Messages/Logs

Steps to Reproduce

Steps to reproduce
Open any project in VS Code with the Claude Code extension installed.
Open a file and place the cursor in it, or select some text.
Open/focus the Claude Code panel and send a message.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.205

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_