Compiz related colour-swapping bug (Endianness bug somewhere)

[geppo61]

Hello,
I suspect a endianness problem in this BigEndian Machine (Apple PowerBook G4 with ATI Radeon Mobility 9700). The same architecture (bigEndian) shows no this specific issue on PowerMac G5 Quad with PCI-Express ATI Radeon HD4670 with VGA BIOS (not powerpc flashed card).

The problem seems to be a screen changing resolution or similar having Compiz activated. If I switch the screen resolution on this laptop, the garbage on the screen is more visible than using NO COMPOSITE Marco Mate Display Manager.

The problem is enhanced using a second monitor attached to a DVI connector on this laptop.

Can be easly reproduced.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: xorg 1:7.7+13ubuntu3
ProcVersionSignature: Ubuntu 4.4.0-116.140-powerpc-smp 4.4.98
Uname: Linux 4.4.0-116-powerpc-smp ppc
ApportVersion: 2.20.1-0ubuntu2.15
Architecture: powerpc
CurrentDesktop: MATE
Date: Fri Feb 23 14:01:47 2018
InstallationDate: Installed on 2018-02-21 (2 days ago)
InstallationMedia: Ubuntu-MATE 16.04.1 LTS "Xenial Xerus" - Release powerpc (20160719)
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)

[geppo61 (icjtqr-gmail)]

This is more visible. When selecting the window, the problem disappears. Some refresh issue?