Windows have grey traces in Ubiquity

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/924909

Please clarify this report. The background when the cd stops is black is not a bug. That is the color used in the Xubuntu installer for the background. Since we want to differentiate between Ubuntu and Xubuntu installs, making the background black was the simplest color to use.

I confirm this with Xubuntu Desktop i386 and amd64.

On the screen 'Try or Install Ubuntu' if the user moves the window, the background doesn't repaint and the window leaves a trail.

I made a video to show what actually happens:

http://youtu.be/WBxql1EwbPw

The video is two minutes long, but actually only the last 30 seconds are relevant.

same problem with the slideshow during a wubi installation

Still present on beta 1.
Now, at least, we have xubuntu wallpaper as background instead of a black screen.

Confirmed using Beta 2 build 20120323

Isn't this a window manager bug rather than a ubiquity bug? (Or, I suppose, a bug in how ubiquity-dm is starting the window manager ...)

It works just fineafter ubiquity screen. So, I don't think it's a windows manager bug.

I get a similar behaviour testing Ubuntu i386 using live usb. The issue doesn't appear on ubiquity window but under a notification one during desktop loading.

1) In Ubiquity, select the language and click on Try Ubuntu.
2) During desktop loading there is just the background on the screen.
3) Then a notification window appears and it shows the issue. (see screenshot)

Do you think it could be the same bug or it's better I open another bug report?

This attachment shows what the artifacts look like on the screen. They are still present in the 20 Apr ISO images.

I have to agree with cjwatson on this one, this looks like a classical window-manager compositing problem to me. Although I would emphasize what you wrote in brackets, it's most likely a problem of how ubiquity-dm starts the window-manager...

Maybe we can work around this by starting xfwm4 without compositing for ubiquity-dm?

Agreed on Colin and Simon on this one. I can also confirm that this happens only in the Ubiquity installer if I don't "try Xubuntu" first, so looks even more like a startup problem.

There should probably be a task for whatever window manager lubuntu uses or provides this:

            elif osextras.find_on_path('openbox-lubuntu'):
                wm_cmd = ['openbox-lubuntu']

I'd guess openbox but I'm not 100% certain.

Still there in Quantal Alpha 2.

I just tested a patch that is now in a branch, switching off the compositor of Xfwm4 in ubiquity-dm.
(See attached screenshot from a live-session of Xubuntu Quantal in VirtualBox.)

Adding openbox for Lubuntu. But I can't reproduce it on a VM, and the solution Simon mentioned can't be apply to openbox since there is no compositor enable for it.

Fixed for me on Xubuntu Quantal Final.

According to comment #20, the problem has been fixed in Xubuntu 12.10. Therefore, it should be fixed in newer releases of Xubuntu too. Can anyone confirm this?