224376 - Hall of mirrors effect during window enlargement when scroll bar at extreme end

Status: RESOLVED FIXED

(Firefox :: General, defect)

Description

[Wayne Woods]

User-Agent:       Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.6a) Gecko/20031029 Firebird/0.7+
Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.6a) Gecko/20031029 Firebird/0.7+

If one or both of the browser scroll bars exist, and one or both of them are set
to the "far end" (bottom for vertical, right for horizontal), then a weird
ghosting or "hall of mirrors" effect occurs when the window is resized to make
its area larger. This includes either dragging the window resizer in the corner,
clicking the maximize/zoom button on the title bar, or simply removing the
status bar from view (which results in a larger window area). The former method
will cause the "hall of mirrors" effect, where dozens of replications of the
window border will occur. The latter two usually only cause a single duplication
of part of the window. Any movement of the scroll bars seems to redraw the
window and remove the buggy appearance.

Setting the vertical bar to the bottom only seems to cause ghosting when the
window is enlarged in a vertical direction, and the horizontal bar affects
enlargement in the horizontal direction.

On occasional windows, this doesn't occur, but instead, it shows a "grey area"
at the far edge(s) of the web page. This isn't nearly as common as the above
effect though.

Reproducible: Always

Steps to Reproduce:
1.Navigate to a web page, e.g. http://www.mozilla.org
2.Shrink the web page (if necessary) until one or both scroll bars appear
3.Move one or both scroll bars to their extreme end, i.e. bottom for vertical or
far right for horizontal.
4.Click on the window resizer in the bottom and drag outwards to enlarge the
window area
5.Observe the "hall of mirrors" effect on the far right or bottom of the window
Actual Results:  
Window edges are duplicated, often many times

Expected Results:  
Resized the window with no duplications or artifacts

I originally reported this effect in bug 223211 ('extra scroll arrow'), but I
suspect it's not actually related at all. Might also be related to bug 215362
('scroll arrows partially hidden'), but I think that's a different problem as well.

Comment 1

[Jonathan Louie]

Attachment: screenshot

Comment 2

[Jason Barnabe (np)]

WFM Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.6a) Gecko/20031107
Firebird/0.7+

Comment 3

[Wayne Woods]

Yeah, it's definitely a Mac-only bug :)

Comment 4

[Wayne Woods]

It seems to have been quietly fixed between the 20040112 and 20040114 builds.
Anyone know any more? :)

Comment 5

[Wayne Woods]

Upon further investigation, it looks like this bug was probably a dupe of the
Seamonkey bug 222300, which was fixed at that time. Never managed to reproduce
this effect on Seamonkey though, so I never noticed the other bug before.