BeforeCapture missing 'type' and 'source' fields. how to know droppable info in the onBeforeCapture?

[hexwit]

From the source code I see that BeforeCapture event has no very important fields like 'type' and 'source'. onBeforeCapture is the only one place, where DOM modification can be applied before dimensions are collected. And here we know the draggableId but we don't know source droppable information?

Am I missing something, or why that info is missing? I believe it is available at a moment of onBeforeCapture.