Hi @gkremer,
Thank you for reporting this problem. We already have this one on our issue-board https://github.com/handsontable/handsontable/issues/4296 - related to beforeOnCellMouseOver and afterOnCellMouseOver. Unfortunately, we didn’t schedule work on fixing it yet. You can track progress by subscribing to notifications from that issue on GitHub or opting into our newsletter in https://my.handsontable.com.
Thank you for your involvement in improving Handsontable!