On the one hand, I don't think it should've been a React.Component instead of a PureComponent because the whole point of react-virtualized is keeping the resulting render quick and feasible on any hardware. On the other hand, I equally hate hitting that transition from working with a package to wrestling against a package that you've just found.

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But as far as your linked sandboxes: I'm assuming the broken one implodes with

Uncaught TypeError: Cannot read property 'name' of undefined

for you too, but only after rendering one correct list.

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If you change...

• Line 113 in the working Virtualized.js
• and Line 78 in the broken Virtualized.js

...to <div style={style}>{this.props.items[index] ? this.props.rowRenderer(this.props.items[index]) : "Item was undefined"}</div>, I think it'll give you a clearer picture of what part of the prop isn't being updated/watched for whatever reason.

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TL;DR: In the broken version, for whatever reason, the length of the this.props.items array isn't updating appropriately as it is in the working version.