[BUG] Vertical conversation scrollbar thumb/down-arrow hidden by bottom fade gradient (.messageGradient_07S1Yg) on dark themes

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?

In the conversation area of my Visual Studio Code IDE, the right vertical scrollbar has a gradient at the bottom. When using a dark theme, the gradient hides the down arrow. As the history increases, the scrollbar thumb shinks. When it gets small enough, the gradient fully covers it as well.

The attached image shows my horizontal scrollbar is visible, but the vertical scrollbar is so faint as to appear non-existent. I had Claude fix it for me in my current version, but any subsequent releases will overwrite this repair. I've also attached the bug report file Claude created for me.

claude-code-scrollbar-bug-report.md

<img width="1557" height="1025" alt="Image" src="https://github.com/user-attachments/assets/f8e789e8-2e2c-4147-b580-734dae85ca95" />

What Should Happen?

The vertical scrollbar thumb and down arrow should be visible at the bottom of the conversation window. Attached is an image of what the scrollbar should look like after Claude fixed it.

<img width="1563" height="1022" alt="Image" src="https://github.com/user-attachments/assets/fe009269-1331-4441-91dc-ab1950ea6023" />

Error Messages/Logs

Steps to Reproduce

1. Enable the Claude Conversation Window in VS Code with a dark theme.
2. Note the vertical scrollbar down arrow does not exists/is incredibly faint.
3. Add a significant conversation history.
4. Note the vertical scrollbar thumb has disappeared/is incredibly faint.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Unknown. I have not seen it work.

Claude Code Version

2.1.162 (Claude Code)

Platform

AWS Bedrock

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_