Scrollbar not visible in Select dropdown on content overflow (visible if options > 10)

[prajwalkulkarni]

Reproduction link

https://stackblitz.com/edit/react-mnyapj?file=demo.tsx

Steps to reproduce

1. Use <Select> component with <=10 options.
2. To see the last option, we will have to scroll, although it is scrollable, the scrollbar is not visible.
3. Or, Implement a custom list item, if the height of each list item is large enough, say 50px, overflow occurs on 4-5 options, but the scrollbar is not visible until there are more than 10 options.

What is expected?

Scrollbar should be visible on overflow, regardless of the number of options available.

What is actually happening?

Scrollbar is not visible unless there are more than 10 options.

Environment	Info
antd	4.24.9
React	17.x
System	Windows 11
Browser	Chrome version 121.0.6167.140

---

For custom list item implementation, it looks like the issue is due to not passing the optional listItemHeight, as the default values are passed and rc-virtual-list is determining whether or not to show the scrollbar with one of the conditions being itemHeight * data.length > height (https://github.com/react-component/virtual-list/blob/master/src/List.tsx)
The prop listItemHeight can be made mandatory when a custom list item is implemented, i.e., children is passed.
Regarding, the regular select option, I think the above condition is returning false (itemHeight * data.length > height) default values of itemHeight being 20 and height being 200.

[stackblitz]

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• react-mnyapj (Open reproduction)

[afc163]

Fixed in #47050

[prajwalkulkarni]

That still wouldn't work on custom list item, right?

[afc163]

It is not released yet.