When selecting icons from the palette, there were no issues with dragging. However, when trying to move or connect pre-existing nodes or connectors by dragging, the drag operation sometimes fails to maintain its hold and drops prematurely.
Please refer to the attached file for more details.
VGVivisa Ganesan Syncfusion Team March 22, 2023 04:01 PM UTC
The cursor hovers on the tooltip while dragging the node, causing the mouseup event to be triggered. To avoid this refer material theme file in index.html file mentioned below. This will resolve your issue. Please find the sample below.