185555 - 8x6px textless tooltip shows after D&D a link from one browser window to another

Status: NEW

(Core :: XUL, defect)

Description

[John Morrison]

An 8x6px textless tooltip shows up after you D&D a link from one browser 
window to another, at least for the steps to reproduce below.

1) open two browser windows, and position them so that they are partially   
   overlapped
2) Load http://us.imdb.com/Title?0120570 into the window on the right.
3) Scroll down to the list of actors.
4) Drag one of the actor links from the right browser window, and drop it
   into the left browser window. (Do not move the mouse any further).

Actual results:
Small, textless tooltip appears at end of page load, usually a few inches up
from the mouse position. This is almost 100% reproducible for me on win2k with
an opt. trunk build pulled Saturday evening.

Expected results:
Don't show the tooltip.

This is possibly related to the timer changes (both the low-level changes and
the changes to nsXULTooltipListener.cpp that I made). I don't think there is 
anything wrong with the changes I made, but this may be exposing a bug with
timers (famous-last-words-what-blame-me?).

[Also, this may possibly have something to do with the random tooltip crashes
that have been reported for Mac OS/X and BeOS (although not reported on win32
or linux, to my knowledge)].

I'll try to look further at this when I have time.

Comment 1

[QA timeless]

this also happens on linux-qt :)