457575 - Transparent PNGs and GIFs appears washed out in Firefox 3 on Linux

Status: RESOLVED DUPLICATE of bug 411831

(Core :: Graphics: ImageLib, defect)

Description

[Håvar I. Henriksen [:havarh]]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; nb-NO; rv:1.9.0.3) Gecko/2008092416 Firefox/3.0.3 Non-sensitiveDataConfirmation/1.F.0
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; nb-NO; rv:1.9.0.3) Gecko/2008092416 Firefox/3.0.3

Transparent PNGs and GIFs is displayed washed out in Firefox 3 on Kubuntu 7.10 with the official Firefox 3 build.
It seems like the problem only occurs on images bigger than 253x253 pixels.
If the image is displayed on a white background, the image is completely invisible while it looks normal if the image is displayed on a black background. The image looks washed out if displayend on any other colored background.
(I guess the problem will go away when I upgrade to Kubuntu 8.04 or 8.10)
The same problem has been reported at:
http://support.mozilla.com/tiki-view_forum_thread.php?forumId=1&comments_parentId=82343
As seen in the report above, the same problem occurs on both SUSE Linux 10.3 64 bit build, Fedora Core amd64 build and on various other Linux Distros.
These problmes do not occur in either Firefox 2 or Konqueror.
I will post testcases and screenshots later. 

Reproducible: Always

Comment 1

[Håvar I. Henriksen [:havarh]]

Attachment: Screenshot showing the problem

Screenshot of:
http://support.mozilla.com/tiki-view_forum_thread.php?forumId=1&comments_parentId=82343
and
http://eriqat.name/BoulevardAutomotive/

Comment 2

[Håvar I. Henriksen [:havarh]]

Attachment: Test case of the PNG problem, with screenshots showing the test in Firefox 3 and Konqueror 3.5.8

Test case of the PNG problem

Comment 3

[Håvar I. Henriksen [:havarh]]

Attachment: Screenshot of the Mozilla Firefox Start Page

Comment 4

[Håvar I. Henriksen [:havarh]]

I tried to recreate this "effect" in GIMP, and I got the same result when using the "Addition" layer mode in GIMP.

Steps I did to make this in GIMP:
1. Opened one of the PNG images from the testcase
2. Added a new green background layer on the image
3. Set the Layer Mode on the top layer to: "Addition"

This made the image look the same as the original image did in Firefox 3...

Comment 5

[Frank Wein [:mcsmurf]]

Does this also happen with an official Firefox build from mozilla.com?

Comment 6

[Håvar I. Henriksen [:havarh]]

(In reply to comment #5)
> Does this also happen with an official Firefox build from mozilla.com?
Yes, as I said in the description, I have been using the official Firefox 3.0.3 build from mozilla.com.
I have tested it with a clean Firefox profile, and I have also tried to disable all the plug-ins, but the problem still occurs.
I have also tested this with the Firefox 3.1a2pre, same problem in this build.

Comment 7

[Frank Wein [:mcsmurf]]

Move to GFX if this is the wrong component, not sure.

Comment 9

[Håvar I. Henriksen [:havarh]]

Ok, the problem seems to be with the nv driver, after either switching to the vesa driver or by following the tips in the bug 411831 by adding this option:
        Option          "XaaNoOffscreenPixmaps" "on"
to the xorg.conf file, the problems goes away.