bug(aria/grid): Selection performance degrades with larger grids

[simonstaffgenius]

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

I really like the new angular/aria grid and how it works.
However, the performance of the grid selection mode deteriorates quickly when rendering larger grids (e.g., 50 × 50 cells). Selecting cells feels laggy and not smooth enough.

Reproduction

StackBlitz link: https://stackblitz.com/edit/stackblitz-starters-project-21version-zzmxctcd?file=src%2Fmain.ts
Steps to reproduce:

1. Wait for the grid to fully load.
2. Start selecting multiple cells.
3. Notice the lag and decreased responsiveness.

Expected Behavior

Grid selection should remain smooth and responsive, even when handling a few thousand cells.

Actual Behavior

The grid selection is laggy.

Environment

• Angular: 21.1.1
• Browser(s): Chrome
• Operating System macOS:

[crisbeto]

Can you try the 21.1.2 release? We released #32705 which is related.

[simonstaffgenius]

Thanks for the quick reply. I’ve tested 21.1.2 as well, and the multi-selection issue persists.