[BUG] Horizontal scrollbar appears in panel mode due to missing horizontal padding in webview container

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 Claude Code is configured with "claudeCode.preferredLocation": "panel" and VS Code is running a multi-pane grid layout, a horizontal scrollbar appears at the bottom of each Claude Code panel. The scrollbar is not caused by content overflow from long lines — it appears to be the webview container itself being a few pixels wider than its available space, with no horizontal padding to absorb the difference.

What Should Happen?

No horizontal scrollbar. A small amount of horizontal padding (e.g. padding: 0 8px) on the webview container would prevent the overflow from triggering the scrollbar.

Error Messages/Logs

Steps to Reproduce

1. Set "claudeCode.preferredLocation": "panel" in VS Code settings
2. Open 2 or more editor groups (e.g. a 2x2 grid layout)
3. Open Claude Code in each panel
4. Observe horizontal scrollbar at the bottom of each Claude Code pane

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.112

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

• "editor.scrollbar.horizontal": "hidden" does not affect the scrollbar as it is inside the webview sandbox
• CSS injection via Apc Customize UI++ and vscode-custom-css cannot reach inside the webview iframe
• The scrollbar disappears if the panel is given additional width, confirming it is a few-pixel overflow issue rather than a content wrapping problem
• Suggested fix: add padding: 0 8px or similar to the Claude Code webview container element