Vertical scroll bar always appears in chat panel

[JasonWeill]

Description

In the Jupyter AI chat UI, a vertical scroll bar always appears, even if the content of the chat UI's messages panel fits entirely in the space provided:

Reproduce

1. Open JupyterLab with Jupyter AI enabled.
2. Open the chat panel.
3. The chat panel shows a message and a scroll bar, even if the message fits entirely in the space provided.

Expected behavior

When the message fits entirely in the space provided, there is no visible scroll bar.

Context

• Operating System and version: macOS 12.6.6 "Monterey"
• Browser and version: Firefox 102.12.0esr, Chrome 114.0.5735.198
• JupyterLab version: 3.6.3

Troubleshoot Output

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Command Line Output

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Browser Output

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