When both virtual scrolling and grouping are enabled via the kendoGridGroupBinding directive, and the Grid is navigable, focus is trapped in the header row when down or up arrow is pressed:

https://stackblitz.com/edit/angular-icxejq?file=app/app.component.ts

1. Focus any content cell

2. Press up/down - focus goes to the header cell of the respective column and is trapped in the header row