dragAndDrop

* dragAndDrop.dropEffect는 data-dropEffect attribute 가 없을 경우 기본설정으로 동작
*. dragAndDrop.dropEffect 와 data-dropEffect 가 없는 경우 null로 전체 허용으로 처리
*. chrome mobile (88.0.4324.152)에서는 event.dataTransfer.effectAllowed 를 설정해도 강제로 copyMove 로 변경된다.
*. 모바일일 경우 effectAllowed 사용에 주의

1
draggable:O
dropzone:O
dropEffect:copy

2
draggable:X
dropzone:X
dropEffect:

3
draggable:X
dropzone:O
dropEffect:move

4
draggable:O
dropzone:X
dropEffect:

5
draggable:O
dropzone:O
dropEffect:link

6
draggable:O
dropzone:O
dropEffect:none

7
draggable:O
dropzone:O
dropEffect:

8
draggable:O
dropzone:O
dropEffect:

9
draggable:O
dropzone:O
dropEffect:

1
draggable:O
dropzone:O

2
draggable:X
dropzone:X

3
draggable:X
dropzone:O

4
draggable:O
dropzone:X

5
draggable:O
dropzone:O

6
draggable:O
dropzone:O

7
draggable:O
dropzone:O

8
draggable:O
dropzone:O

9
draggable:O
dropzone:O