Resize Divider Misalignment with Nested Columns in layoutMode="grid"

[dcaudillo99]

material-react-table version

v3.2.0

react & react-dom versions

v19.0.0

Describe the bug and the steps to reproduce it

When using layoutMode="grid" with nested columns, the resize divider for the parent column becomes misaligned if the child columns use different grow values. Specifically, when one child has grow: false, and another has grow: true, the parent resize handle does not line up correctly with the combined width of its children.

This causes visual and functional inconsistency when resizing grouped columns.

Expected Behavior
The parent resize divider should align correctly with the total width of its child columns, regardless of their individual grow values.

Actual Behavior
The resize divider for the parent column becomes offset and does not match the layout of the nested child columns.

Minimal, Reproducible Example - (Optional, but Recommended)

Codesandbox: https://codesandbox.io/p/devbox/nifty-tree-wry69j?file=%2Fsrc%2FTS.tsx

Screenshots or Videos (Optional)

Do you intend to try to help solve this bug with your own PR?

None

Terms

• I understand that if my bug cannot be reliably reproduced in a debuggable environment, it will probably not be fixed and this issue may even be closed.