Mouse cursor size changes based on what's under it

[cdawg]

I have a Lenovo P51 with Nvidia card. 4k display in the laptop and 2 2560x1440 external monitors. The mouse cursor changes between a normal size and a much much larger size when it is over the background and over some application's title bars. Other times it is normal size.

I have wiped my gnome 3 settings and re-set all the cursor size settings to default but nothing helps. I assume it's HiDPI related.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xorg 1:7.7+19ubuntu7
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Uname: Linux 4.15.0-20-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
.proc.driver.nvidia.gpus.0000.01.00.0: Error: [Errno 21] Is a directory: '/proc/driver/nvidia/gpus/0000:01:00.0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 390.48 Thu Mar 22 00:42:57 PDT 2018
 GCC version: gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: GNOME
Date: Mon May 14 09:08:47 2018
DistUpgraded: 2018-05-13 09:36:57,549 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py'
DistroCodename: bionic
DistroVariant: ubuntu
DkmsStatus:
 fwts-efi-runtime-dkms, 18.03.00, 4.13.0-41-generic, x86_64: installed
 fwts-efi-runtime-dkms, 18.03.00, 4.15.0-20-generic, x86_64: installed
 nvidia, 390.48, 4.15.0-20-generic, x86_64: installed
 virtualbox, 5.2.10, 4.15.0-20-generic, x86_64: installed
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation Device [8086:591b] (rev 04) (prog-if 00 [VGA controller])
   Subsystem: Lenovo Device [17aa:224d]
   Subsystem: Lenovo GM107GLM [Quadro M1200 Mobile] [17aa:224d]
InstallationDate: Installed on 2017-12-29 (135 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Release amd64 (20171018)
MachineType: LENOVO 20HHCTO1WW
ProcEnviron:
 LANGUAGE=en_CA:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_CA.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-20-generic root=/dev/mapper/ubuntu--vg-root ro acpi_osi=
SourcePackage: xorg
Symptom: display
UpgradeStatus: Upgraded to bionic on 2018-05-13 (0 days ago)
dmi.bios.date: 02/26/2018
dmi.bios.vendor: LENOVO
dmi.bios.version: N1UET46W (1.20 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20HHCTO1WW
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40697 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrN1UET46W(1.20):bd02/26/2018:svnLENOVO:pn20HHCTO1WW:pvrThinkPadP51:rvnLENOVO:rn20HHCTO1WW:rvrSDK0J40697WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.family: ThinkPad P51
dmi.product.name: 20HHCTO1WW
dmi.product.version: ThinkPad P51
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.13.1+18.04.20180302-0ubuntu1
version.libdrm2: libdrm2 2.4.91-2
version.libgl1-mesa-dri: libgl1-mesa-dri 18.0.0~rc5-1ubuntu1
version.libgl1-mesa-glx: libgl1-mesa-glx 18.0.0~rc5-1ubuntu1
version.nvidia-graphics-drivers: nvidia-graphics-drivers-* N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.19.6-1ubuntu4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.0.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau N/A
xserver.bootTime: Mon May 14 08:17:52 2018
xserver.configfile: default
xserver.errors:
 Failed to load module "nouveau" (module does not exist, 0)
 Failed to load module "nouveau" (module does not exist, 0)
xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.19.6-1ubuntu4

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.