260968 - Page is not properly refreshed on scrolling up/down if there is (a) Flash content and a (b) "position:fixed" element present.

Status: RESOLVED WORKSFORME

(Firefox :: General, defect)

Description

[Baldur Kristinsson]

User-Agent:       Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; rv:1.7.3) Gecko/20040913 Firefox/0.10
Build Identifier: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; rv:1.7.3) Gecko/20040913 Firefox/0.10

On scrolling up/down, you see "shadows" of Flash animations (normally gray
rectangles or still frames from the Flash movie) being redisplayed in the same
x-position on the new page (normally in the screen position the flash animation
was at before the scroll). This occurs whether you use the mouse, the scroll bar
or the keyboard to scroll. Tests have shown that if the div containing the ad on
the right (which has "position: fixed") is changed to "position: absolute", the
problem goes away. It does not matter what the content in the fixed div is.

The problem has been seen in both Firefox 0.9.3 and 1.0PR on MacOS X. In both
cases Flash plugin 7.0 was being used. The problem has not been observed in
Linux or Windows. It has not been seen in Camino 0.8 for OS X either.

It sounds similar to bug 256480 (despite a different OS) - perhaps it is related?

Reproducible: Always
Steps to Reproduce:
1. Go to the referenced web page.
2. (If necessary:) Refresh the page until you see some flash content (ads) in
the main part of the page.
3. Scroll down the page.
Actual Results:  
There are gray rectangles and/or still frames from the Flash being displayed on
top of normal content.

Expected Results:  
The page should have been displayed without any "shadow" flash content.

Comment 1

[Baldur Kristinsson]

The example page http://www.mbl.is/mm/frettir/ has been changed slightly to
force refresh using javascript. In order to properly see the problem either (a)
switch javascript off temporarily; or (b) change the User-Agent string so that
it no longer matches the regular expression "/Mac OS X .* Gecko\/2004/".

Comment 2

[Baldur Kristinsson]

The problem also occurs in Mozilla 1.7.3 on Mac OS X.

Comment 3

[Hiro]

wfm.
Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; ja-JP; rv:1.8b) Gecko/20050204
Firefox/1.0+

Comment 4

[José Jeria]

Also WFM: Mozilla/5.0 (Macintosh; U; PPC Mac OS X Mach-O; en-US; rv:1.8b)
Gecko/20050205 Firefox/1.0+

Please reopen if you can reproduce with a nightly build.

Comment 5

[Baldur Kristinsson]

The bug is still present. Some browser-specific javascript in the page just  
makes it slightly harder to reproduce it.  
  
Re comments #3 and #4: You probably tested by switching to a user-agent string  
corresponding to MSIE 6.0 on Windows. As IE does not support position:fixed,  
the page uses a javascript workaround in this case, defining the ad position  
as absolute rather than fixed (in fact the same workaround as for recent Gecko  
browsers on OS X).  
  
Please perform further tests with the user-agent string set to a different  
browser, for instance Firefox on Linux or Opera on Windows. 
 
I tested with the Firefox nightly build for OS X, downloaded 2005-02-10; Gecko 
build date 20050209. 

Comment 6

[WD]

Reporter:  Do you have Adblock installed?
If so, this appears to be an Adblock bug...

A good test page is: http://www.mikedoughty.com/show_dates/

Comment 7

[Gervase Markham [:gerv]]

This is an automated message, with ID "auto-resolve01".

This bug has had no comments for a long time. Statistically, we have found that
bug reports that have not been confirmed by a second user after three months are
highly unlikely to be the source of a fix to the code.

While your input is very important to us, our resources are limited and so we
are asking for your help in focussing our efforts. If you can still reproduce
this problem in the latest version of the product (see below for how to obtain a
copy) or, for feature requests, if it's not present in the latest version and
you still believe we should implement it, please visit the URL of this bug
(given at the top of this mail) and add a comment to that effect, giving more
reproduction information if you have it.

If it is not a problem any longer, you need take no action. If this bug is not
changed in any way in the next two weeks, it will be automatically resolved.
Thank you for your help in this matter.

The latest beta releases can be obtained from:
Firefox:     http://www.mozilla.org/projects/firefox/
Thunderbird: http://www.mozilla.org/products/thunderbird/releases/1.5beta1.html
Seamonkey:   http://www.mozilla.org/projects/seamonkey/

Comment 8

[Baldur Kristinsson]

Fixed in Firefox 1.5 Beta 1.

Comment 9

[José Jeria]

Reopening to fix resolution --> wfm