issue/696 : Multigrid falls out of sync with 50k+ items when scrollbars are on.

[MIKL99999]

• Remove additionalRowCount.
• When bottomRightGrid has scrollbar add height style to bottomLeftGrid
  to compensate the difference of grids containers height,
  which appears due scrollbar size.
• Fix MultiGrid test.

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[jeremyk]

Any updates on this? We are seeing this issue as well.

[MIKL99999]

@jeremyk
No answer from maintainers, yet.
As a hotfix, you can inherit from MultiGrid class and override changed methods.

[jeremyk]

Thanks, I will try that.

[jeremyk]

@MIKL99999 - I tried your but it caused other bugs in interactions with the scroll bars.

[MIKL99999]

@jeremyk Can you describe those bugs?

[bvaughn]

Sorry for the very long delay in getting back to you about this!

I've just finished a large update for version 10 of react-virtualized (#1900): the library has been rewritten in TypeScript, every component is now a function component (React 18+ is required), and the source moved from source/ to lib/. Because of that, this PR can't be merged as-is. Version 10's MultiGrid still uses the spacer row approach, though offsets are now only scaled above about 16.7M px, so the 50k-row repro from #696 may behave differently now.

If you're still interested in this change, I'd welcome a new PR with it rebased onto the version-10 branch (or onto master once version 10 has been merged).