[BUG]: Chat panel renders black/blank in v2.1.161 (regression from v2.1.160)

[nvsmee001-coder]

Preflight Checklist

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

What's Wrong?

After updating to v2.1.161, the main chat webview panel is completely black/blank. The conversation area and input box are invisible. The panel opens but shows only a black screen.

What Should Happen?

The chat panel should render normally, showing the conversation area and input box, as it did in v2.1.160.

Error Messages/Logs

No error messages shown. Extension activates normally, authentication succeeds, MCP servers connect — issue is purely visual in the webview render layer.

From extension log (Claude VSCode.log):
- AuthManager initialized ✓
- Claude code extension is now active ✓
- MCP Server running ✓
- OAuth tokens found in secure storage ✓
- Webview receives and sends messages normally ✓
- Only the visual chat panel is black

Steps to Reproduce

1. Install Claude Code extension v2.1.161 on Antigravity IDE (Windows)
2. Open any workspace
3. Open Claude Code panel
4. Chat panel renders completely black — no input box, no conversation area visible
5. Downgrade to v2.1.160 → panel renders correctly

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.160

Claude Code Version

2.1.161

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

IDE: Antigravity IDE (VS Code-based fork), Windows 11 Pro 10.0.26200

Technical finding: webview/index.js in v2.1.161 has the same file size as v2.1.160 (4,812,645 bytes) but a different MD5 hash — content was modified in-place. Suspected cause: the animation/"Reduce Motion" compliance fix introduced in v2.1.161 may have broken the webview render.

Everything else works: Ping ✓, CLI ✓, Auth ✓, MCP ✓. Only the chat panel UI is affected.