window titlebar is disturbed on all non-maximized windows

[Guido Jäkel]

* After todays package update, the window titlebar area of all windows is rendered in a disturbed way.
* Package update include a kernel change to 5.3 from 5.0. The bug is not related to the kernel; it also happen with the last one. Therefore, it's related to the new graphic packages.
* This don't happen if the window is maximized.
* This was also on a second PC with idential hardware (Dell 755 & Radeon HD 6450 video card)

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-image-5.3.0-26-generic 5.3.0-26.28~18.04.1
ProcVersionSignature: Ubuntu 5.3.0-26.28~18.04.1-generic 5.3.13
Uname: Linux 5.3.0-26-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.9
Architecture: amd64
CurrentDesktop: Unity:Unity7:ubuntu
Date: Sun Jan 19 12:44:46 2020
SourcePackage: linux-signed-hwe
UpgradeStatus: No upgrade log present (probably fresh install)

[Guido Jäkel (guido-jaekel)]

gjaekel@jelly:~$ lshw -C video
WARNING: you should run this program as super-user.
  *-display
       description: VGA compatible controller
       product: Caicos [Radeon HD 6450/7450/8450 / R5 230 OEM]
       vendor: Advanced Micro Devices, Inc. [AMD/ATI]
       physical id: 0
       bus info: pci@0000:01:00.0
       version: 00
       width: 64 bits
       clock: 33MHz
       capabilities: vga_controller bus_master cap_list rom
       configuration: driver=radeon latency=0
       resources: irq:31 memory:d0000000-dfffffff memory:fe9e0000-fe9fffff ioport:dc00(size=256) memory:c0000-dffff

[Guido Jäkel (guido-jaekel)]

Also, some other desktop elements like tooltips, drop down lists or even the selection rubberband box of the screenshot feature are affected. It seems, that the the similarity of this is a comparable small *height*. The rubberband selection for instance is disturbed, if the enclosed height is about less than a few lines and this is totally independent from the width.

For comparison, I create some squares with a bitmap editor: The quirks seems to have "shifted" band sections with a height of 8px. It disappear, if the height reaches about 8*8px. More exact, it aligned to height mod 8 and disappear, if (upper-lower) mod 8 >= 8.

[Guido Jäkel (guido-jaekel)]

was fixed for me with common Ubuntu updates related to bug #1841718.