Fixed column header with rounded corners cannot cover the rows behind while scrolling

What problem does this feature solve?

https://codesandbox.io/p/sandbox/fixed-columns-antd-5-12-3-rzkvhl

This issue can be reproduced in official demo also. The column 'Action' has rounded corner, while scrolling rows horizontally and the row behind will be exposed through the rounded

before scrolling horizontally:

after scrolling, and the rounded corner disappeared

What does the proposed API look like?

The corners with border radius can fully cover rows under it.