When using row virtualization, the visible rows are miscalculated when the browser zoom is used (hold control with mouse scroll).
The result of the miscalculation is that the first row at some point is not visible.
To reproduce the problem you should scroll to the top of the grid and see the first row.
Then start to zoom down and see how the first row is displaced.
Seems like only 50%, 100%, 150%, 200% (multiply of 50%) are calculated correctly in row virtualization
You can reproduce the bug with the attached code.
It's browser-specific and is appearing only in chromium browsers.
It could be related to the way browsers calculate the size of the elements when zooming.
Currently, there is an open bug in the chromium: https://bugs.chromium.org/p/chromium/issues/detail?id=1048147&q=component%3AUI%3EBrowser%3EZoom%20height&can=2