176297 - Long SELECT tag drawn incorrectly when scrolling slowly with animated GIFs

Status: RESOLVED WORKSFORME

(Camino Graveyard :: HTML Form Controls, defect, P3)

Description

[Michael Lam]

User-Agent:       Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en-US; rv:1.0.1) Gecko/20021022 Chimera/0.5+
Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en-US; rv:1.0.1) Gecko/20021022 Chimera/0.5+

In the traditional chinese newspaper page 
appledaily.atnext.com, there is a very long subject SELECT tag. When opening the
menu for the SELECT tag and scroll slowly using the mouse pointer, the menu is
drawn incorrectly and some of the options for the SELECT tag is overlapping each
other. Re-opening the menu fix the problem.
The problem does not occurs when the scrolling is fast enough.

This bug actually happens for a long time, I am testing on build
2002-10-24 and using Mac OS X 10.2.1 and it can reproduce the problem. I am also
experiencing the problem before I've upgraded to 10.2 and using a earlier build.

Reproducible: Always

Steps to Reproduce:
1.Go to the website appledaily.atnext.com
2.Select on the SELECT tag, a large list will appear normally. (The list changes
daily)
3.Move the mouse pointer to just above the "Down" arrow key in the menu to make
the menu start scrolling slowly.

Actual Results:  
The menu scrolls, after a moment, the menu items starts to overlap and drawn on
each other.

Expected Results:  
The menu should scroll perfectly.

Comment 1

[Greg K.]

WorksForMe using Chimera/2002102204 on 10.1.5.

Comment 2

[Michael Lam]

Try using OSX 10.2.1.

The bug happens when a very slow scrolling occurs. Maybe I'll try to grab a screenshot.

Comment 3

[Stephane Moureau]

WFM under 1026 OS X 10.1.5. Not slow and normal.
However the pop opened with the menu visible contains some characters (2) which
are shown as black square in the menu. But they are shown correctly (chinese
font) when they are the selected items in the popup. They are also shown
correctly in View Source.
The font in View Source seems different than usual (for english text), but it's
perhaps it's needed to show chinese characters.
<option value="2912085">&#12288;&#12288;&#20841;&#32769;&#38548;&#22812;&#65533;&#27713;&#20304;&#39151;</option> 5th char = black square
...snip...
<option value="2911852">&#12288;&#12288;&#12300;&#19981;&#22914;&#25536;&#38291;&#22909;&#65533;&#24188;&#31258;&#22290;&#12301;</option> 7th char = black square
When paste in BBEdit char 5 and 7 are shown as hollow white square followed by a
space.

Comment 4

[Michael Lam]

I don't mean that the scrolling of that SELECT tag is SLOW, but I am talking
about when you scroll the SELECT tag SLOWLY, the elements in the select tag is
drawn incorrectly and overlaps each other.
So far I can only reproduce it in OS X 10.2 and 10.2.1, I cannot grap a
screenshot because when I am using GRAB to grab the screenshot, it always does
not includes the SELECT tag menu (I don't know why).
About the squares, personally I think that they are chinese characters that were
made specifically for Hong Kong and may not be included in the normal BIG5
encoding and does not related to the bug.

Can someone who understands traditional chinese characters help me confirming
this bug?

Comment 5

[Chris Platts]

I filed bug 178486 before having this bug brought to my attention by Michael Lam.

I've narrowed things down a little more over there - it seems the presence of an
iframe in *any* other open page (be it another tab or another window - even a
minimized window) causes this corruption.  The contents of the iframe-containing
page is painted over the menu during a scroll, and the text is writing over itself.

This is using western charsets, so it's not Chinese charset-specific.

Comment 6

[Michael Lam]

I've seen some check-ins to do native menu for SELECT tag, maybe it will fix
this bug later.

Comment 7

[Chris Platts]

*** Bug 178486 has been marked as a duplicate of this bug. ***

Comment 8

[Chris Platts]

Here's some info from bug 178486 that may be relevant.

Test URL - http://www.bbc.co.uk/
(page with long <SELECT> list, no iframes / layers (uses tables only)

Test URL -
http://www.gnutellaforums.com/showthread.php?threadid=14741&highlight=UDP+search+architecture
(page with long <SELECT> list at end of page.  Uses iframe for ad content at bottom)

Steps to  reproduce:

1. Close all Navigator windows.
2. Open the BBC page only.  Open the popup menu, scroll slowly - should display
correctly.
3. Open the Gnutella forums page in another window.  Test the Forum Jump menu. 
Scroll menu slowly.  Text is corrupted, and portions of the underlying web page
overwrite the menu.
4. Switch back to the BBC page.  The menu now corrupts on scrolling, with
portions of the Gnutella page overwriting the menu, even with the Gnutella
page's window minimized.

Screenshot forthcoming...

Comment 9

[Chris Platts]

Attachment: Shot showing menu text corruption and redraw issues.

Comment 10

[Michael Lam]

Should someone confirm the bug?

Comment 11

[Stephane Moureau]

Is it not a duplicate of Bug 168757 for select menu instead of menu in menubar ?

Comment 12

[Greg K.]

Marking confirmed per comment 7.

Comment 13

[Matthew D Truch]

another reproduction of the bug: The "country" select on http://www.
mapblast.com/myblastd/

Comment 14

[Simon Fraser [no longer active]]

We need a controlled testcase for this bug. Does it only happen on pages with
plugins, or when a plugin (e.g. Java) is showing in another tab?

Comment 15

[Michael Lam]

The bug seems happens when the page contains plugin or animated gifs.

Comment 16

[Michael Lam]

Just found out that animated gif also causes the issue, as in web site -

http://www.espnstar.com/jsp/cda/sportsonair/tvtimes_legacy.html

Comment 17

[Chris Petersen]

Here is a simple test case from 168757:
A portion of the page with paint on the select menu if first place focus in the
text field (then scroll the menu by clicking on it's top or bottom arrows).


http://bugzilla.mozilla.org/attachment.cgi?id=99246&action=view

Comment 18

[Ludovic Hirlimann [:Usul]]

I can confirml this on Camino buil id 2003082402. My machine is SMP.

Comment 19

[Taral]

WFM on 2005071208, OS X 10.3.9, non-SMP.

Comment 20

[Samuel Sidler (old account; do not CC)]

I can't reproduce with the testcase in comment 17.

Did we fix this somehow or am I understanding it wrong?

Comment 21

[Simon Fraser [no longer active]]

Maybe fixed in Tiger?

Comment 22

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

(In reply to comment #20)
> I can't reproduce with the testcase in comment 17.
> 
> Did we fix this somehow or am I understanding it wrong?

I don't see any animated GIFs in that testcase.  Comment 15 indicates animated
GIFs or plugins are also required.

Comment 23

[Samuel Sidler (old account; do not CC)]

Attachment: Animated GIF for testcase

Linking testcase to this

Comment 24

[Samuel Sidler (old account; do not CC)]

Attachment: Testcase

So, if I'm understanding the bug correctly, this testcase should draw the
select form widget incorrectly. I'm not seeing this at all. It does render
slow, but that's a bug with the animated GIFs.

This WFM.

Comment 25

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

WFM also on 10.3.9.