Grids: top rows become invisible after fast scrolling to top with inertia

[ddaribo]

Description

When scrolling quickly up and down in an igx-grid/ igx-tree-grid, the top rows can occasionally disappear. After a fast momentum/inertia scroll back to the top, the grid visually starts around row 10–15 even though the scroll container reports scrollTop as 0 or near 0.
This appears to be a regression. The same code and configuration works correctly in @infragistics/igniteui-angular@21.0.13.

Framework

Angular

Angular Version

21.x

Ignite UI for Angular Version

21.2.x

Component / Area

Grid

Browser

Chrome

Operating System

No response

Command Not Working

Steps to Reproduce

1. Open this sample

2. Scroll the grid to the bottom by holding the scrollbar.

3. Now scroll back to top by using the momentum of the mouse scroll wheel or the touch pad

4. Observe the top records - some are out of view.

5. Position gets recovered after slightly scrolling down&up afterwards

6. Do the same in this identical sample against version 21.0.13

Actual Result

Expected Result

In 21.0.13:

Reproduction URL

https://stackblitz.com/edit/grid-scroll-sample-xzmhxocs?file=src%2Fapp%2Ftree-grid-primaryforeignkey-sample%2Fdata.ts

Attachments

No response