326026 - Using overflow seems to somehow sandbox events (and change reaction area?)

Status: UNCONFIRMED

(Core :: DOM: UI Events & Focus Handling, defect)

Description

[Bart]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.1) Gecko/20060111 Firefox/1.5.0.1
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.1) Gecko/20060111 Firefox/1.5.0.1

On a previous version of the example page the document
boxes (actually LIs) are draggable just fine.

When the LI's parent (the UL) has overflow set on anthing
but 'visible' (I tried 'scroll', 'auto' and 'hidden'), 
only drags starting over the *text* inside the LI works as 
before/expected. (The page linked to demonstrates this,
it has overflow set)


On that page, when you drag starting from the
empty area inside the LI, only events within 
the same table cell (TD) will fire and none
work in any of the other TDs, not even the
pretty unrelated mouseovers (easy check: they
do all highlighting).  
Dragging from the label still works as before.


Opera works as expected. (IE does too, though it
needs bubble blocking to avoid drags from also
selecting text, despite that the default action
should be prevented.)

Reproducible: Always

Steps to Reproduce:
1. Go to http://www.scarfboy.com/ddtab-somehowblocked.html
2. See what should happen: Start drag from 'doc2' label, to either row, 'verified' column, and notice messages showing that events fire continuously
3. Reload
4. Start drag from 'doc2' but beside label, to either row, 'verified' column
5. Observe lack of events when moving outside of originating TD.

Actual Results:  
No mouseover/mouseout (highlighting), mousedown (dragging) events register.

Expected Results:  
That they register, i.e. behave as in step 2 and in Opera.

Some other bugs seem to be caused by the same thing, like 307792, but I'd have to do a fair bunch of testing on each bug to be sure of that.