- generic [active] [ref=e1]:
  - generic [ref=e2]: source (field 42)
  - generic [ref=e3]: group target
  - generic [ref=e4]: group target 2
  - generic [ref=e5]: "[dragstart] [dragenter target] [dragover target] getData(custom)= \"\" getData(text/plain)= \"\" types= [\"text/plain\",\"application/fms-field\"] effectAllowed= \"copy\" [drop target] getData(custom)= \"42\" getData(text/plain)= \"张三\" types= [\"text/plain\",\"application/fms-field\"] effectAllowed= \"copy\" [dragend] effectAllowed= copy"