493412 - tabbrowser's onDragLeave does not fire reliably

Status: NEW

(Core :: DOM: Copy & Paste and Drag & Drop, defect, P5)

Description

[Jim Mathies [:jimm]]

steps:

1) open two tabs
2) click down on the active tab without moving the mouse
3) tear the tab away quickly

result: tabbrowser's _onDragLeave will never fire.

alternatively:

1) open two tabs
2) click down on the active tab and move the mouse around a little
3) tear the tab away quickly

result: tabbrowser's _onDragLeave will fire.

A way to see this is to enabled the native drag target debug output. Not sure if this is a widget problem or a problem with the drag target setup up in chrome.

Comment 1

[Jim Mathies [:jimm]]

a bug this blocks is wanted for 3.5.

Comment 2

[Dão Gottwald [:dao]]

_onDragOver isn't called in that case either, is it?
Why do you change the cursor in _onDragStart to auto rather than default?

Comment 3

[Jim Mathies [:jimm]]

(In reply to comment #2)
> _onDragOver isn't called in that case either, is it?
> Why do you change the cursor in _onDragStart to auto rather than default?

Doesn't appear to. I wasn't expecting drag over events, but my assumption was you would have to receive the leave event, because technically the cursor has to leave the target at some point.

Comment 4

[Karl Tomlinson (:karlt)]

If the tab is being dragged towards content, bug 481737 means the dragleave does not fire because content has it's own ESM.

Comment 5

[Jens Stutte [:jstutte]]

Bulk-downgrade of unassigned, >=5 years untouched DOM/Storage bugs' priority and severity.

If you have reason to believe this is wrong, please write a comment and ni :jstutte.