Bug 186994

Summary:	Dragging shadow DOM child immediately triggers dragend
Product:	WebKit	Reporter:	Achim <achim.weimert>
Component:	New Bugs	Assignee:	Nobody <webkit-unassigned>
Status:	RESOLVED DUPLICATE
Severity:	Normal	CC:	achim.weimert, rniwa, wenson_hsieh
Priority:	P2
Version:	Safari 11
Hardware:	Mac
OS:	macOS 10.13
Bug Depends on:
Bug Blocks:	148695

Description Achim 2018-06-25 01:38:38 PDT

Hi there,

When setting a Web Component to be draggable and starting the drag operation (via mouse down) on a child of that Web Component within its shadow DOM, the dragstart event is immediately followed by dragend and the drag operation is cancelled. Dragging the shadow DOM host itself works fine.

Simple Example:
https://codepen.io/a-xin/pen/XYBpNG?editors=1001

Environment:
macOS 10.13, Safari 11.1

Other browsers:
Starting the drag operation on either the host or the child works fine in Firefox and Chrome.

Impact:
Drag-and-drop does not work when using Web Components

Comment 1 Ryosuke Niwa 2018-09-20 23:27:51 PDT

Thanks for the bug report! We've identified this bug as a duplicate of the bug 136836.

*** This bug has been marked as a duplicate of bug 136836 ***