composite slowdown on text shift in firefox

[Lotharster]

Binary package hint: kdebase-workspace

To reproduce this bug do the following:

Start firefox and open any web page with plain text visible, e.g. kubuntu.org
Use the mouse to select some lines of text, e.g. the paragraph titled "What is Kubuntu?" (The bug might depend on the amount of text, so on a fast machine a larger text might be needed to reproduce this bug)
Click on the blue-marked text (with the left mousebutton) and hold down the button, while moving the mouse button a bit in any direction.
Release the mouse button

The system will slow down, after some time a message will appear that the composite system was disabled due to a slowdown.

This might also be a bug in firefox, I'm using version 3.0.16 from the ubuntu repos

ProblemType: Bug
Architecture: amd64
Dependencies:

DistroRelease: Ubuntu 9.04
NonfreeKernelModules: fglrx
Package: kwin None [modified: /var/lib/dpkg/info/kwin.list]
ProcEnviron:
 LANGUAGE=
 PATH=(custom, user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: kdebase-workspace
Uname: Linux 2.6.28-17-generic x86_64
UnreportableReason: Das Paket stammt nicht von Ubuntu.

[Jonathan Thomas (echidnaman)]

Probably a driver issue. (Either that or Firefox)

[bugbot (bugbot)]

This bug report was filed against an old version of Ubuntu.
Can you confirm whether this is still an issue in natty?

If you don't mind, it would be very helpful if you could update the bug
report in launchpad to 'Fix Released' if it is no longer an issue for
you, or if it is still occurring under natty, please tag the bug 'natty'
so it's easier for us to track.

[Lotharster (lotharster)]

Fixed in 10.4