Randomly totally broken in Firefox

In Firefox, **sometimes**, react-sortable-tree can get into a totally locked up state. This means that:

1. Dragging doesn't work at all.
2. Visually it looks bad. Non dragged items are thought to be dragged, in the rowCancelPad state.
2. Some static nodes are thought to be 0.5 opacity nodes, like while dragging, but actually they are not dragged.
4. canDrop is actually not called.

The worst part of this is that **reloading the page doesn't solve this issue**. Once a page gets into this state, it'll stay this forever. The only fix is to **open a new tab and close the old one**.

I'm trying to make a reproducible case, but my code is basically node-renderer-default and tree-node-default simplified.

It happens more frequently if I'm clicking on an item quickly after page load.