Demopage cities-dropdown does not work on scroll.
When I open the http://github.hubspot.com/react-select-plus/ demo page and try to use the cities dropdown, scrolling the dropdown, cities start disappearing and soon I'm scrolling a white dropdown. (Chrome Version 60.0.3112.113 (Official Build) (64-bit), OSX 10.12.6)

Our dataset is 10k+ rows, and we most likely need the react-virtualized-select functionality. Without it, react-select-plus was too slow. From the current examples I do not quite understand how to get option groups and virtualized-select both working at the same time. The virtualized demo does not seem to contain groups and also it does not seem to work. :(
Bug confirmed, though it's not on our end—I observe the same glitch in the react-select demo. In fact, both demos actually use react-select rather than react-select-plus, because that's what react-virtualized-select wraps around.
If you want to use react-virtualized-select with react-select-plus, you'll have to reverse-engineer the react-virtualized-select implementation for yourself. It's fairly straightforward.
We should update the docs, since they currently suggest that react-virtualized-select is somehow compatible with react-select-plus (it's not).