Comment 6 for bug 249436

Mike, thanks for the quick response.

> I am on Firefox 3 here (3.0+nobinonly-0ubuntu0.8.04.1) and see the
> original image just as you do in Firefox 2, without the banding, so I
> can't confirm this issue.

Interesting. I thought it may be particular to my setup as I couldn't
find any existing bugs and it seems such an obvious visual abberation.

> What exactly do you mean by a 16bpp root window? I am unaware of what
> that means, but since this doesn't appear to be a universal Firefox
> issue on a standard install, it may be something about your specific
> system setup. Any ideas?

Firstly, I've a bog standard Ubuntu 8.04 Desktop install. I've no
packages from non-Ubuntu respositories, and no non-package software. I
meant above that my X server's root window is 16 bits per pixel. In
other words, my Gnome/X desktop can display 2**16 different colours,
65,536.

This is due to my stalwart old graphics card. Most modern desktop
systems would have 24bpp, but historically 16bpp or even 8bpp desktops
were common. It may be that some PDAs or phones these days still have
16bpp graphics.

Anyway, there's clearly a regression in FF3 over FF2 and its probably to
do with the fact my graphics card has less bits per pixel than most
other FF3 users since you don't see the same issue. Although, given I'd
have thought FF3 just uses a library to do the decompression to a
certain colourspace, I'm puzzled as to why that would have changed
between versions.

Xorg(1) can be started with `-depth 16', or have a look at the
DefaultDepth setting in the Screen section of /etc/X11/xorg.conf.