The cooperation between those plugin hasnât been officially established yet. I will do my best to check what can be done and will update you later today.
I checked if we could use any hook (as nestedRows does not have hook API) and found out that beforeOnCellMouseDown is the only hook that is called when we click the expand/collapse icon in the row header.
So Iâve used it to check if the clicked element is the collapse/expand button
However, the issue is that the parent does not want to expand.
Here is my latest progress Handsontable example - JSFiddle - Code Playground I wasnât able to fix the auto-collapsing effect but I think that this can be the start of a good workaround so I wanted to share it with you.