We had a very strange issue with a project we work on.
Our React app supports drag-and-drop of devices on a floorplan, using react-dnd. Everything works just fine locally and on our servers, but once the UI is deployed to the production machine (that is accessible via intranet), the drag-and-drop stopped working.
Debugging the production UI remotely (via TeamViewer), it seemed that the drag start event was called, but something caused the drag to end right after that.
I immediately assumed that it was TeamViewer causing the issue – even thinking that it was because multiple users were connected to the machine.
Turned out, that the machine had AnyDesk installed and it caused the issue. Closing it made the drag-and-drop work again.