Subject of the issue

Resizing of items in a nested grid does not work correctly

Your environment

gridstack 3.2.0 HTML5
Firefox 85
Chrome 88

Steps to reproduce

Resize an item in the nested grid
https://jsfiddle.net/12L4fsnm/

Expected behavior

Resizing work correctly

Actual behavior

Starts dragging instead resizing

Perhaps this will solve the problem:
e.preventDefault();