cannot run GUI application programs with elevated permissions

This bug appears, when I try to run GUI application programs with elevated permissions using sudo -H and gksudo in an installed Ubuntu Artful system on Wayland.

I discovered it while testing mkusb: version 12 alias mkusb-dus works because the GUI is running as the regular user. Only the executing scripts are running with elevated permissions; version 11 with the classic interface fails.

During the troubleshooting I discovered that no GUI application works. I tested xterm, nautilus and even gparted, which is made to run in graphics mode with elevated permissions, and none of them works.

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tester@tester-SATELLITE-PRO-C850-19W:~$ sudo -H xterm
[sudo] password for tester:
No protocol specified
Warning: This program is an suid-root program or is being run by the root user.
The full text of the error or warning message cannot be safely formatted
in this environment. You may get a more descriptive message by running the
program as a non-root user or by removing the suid bit on the executable.
xterm: Xt error: Can't open display: %s
tester@tester-SATELLITE-PRO-C850-19W:~$ sudo -H nautilus
No protocol specified
Unable to init server: Could not connect: Connection refused

(nautilus:7987): Gtk-WARNING **: cannot open display: :0
tester@tester-SATELLITE-PRO-C850-19W:~$ sudo -H gparted
Created symlink /run/systemd/system/-.mount → /dev/null.
Created symlink /run/systemd/system/media-tester-966d0a59\x2d9e02\x2d45d8\x2d8d27\x2d6916fdf9a4ee.mount → /dev/null.
Created symlink /run/systemd/system/run-user-1000.mount → /dev/null.
Created symlink /run/systemd/system/run-user-120.mount → /dev/null.
Created symlink /run/systemd/system/tmp.mount → /dev/null.
No protocol specified

(gpartedbin:8044): Gtk-WARNING **: cannot open display: :0
Removed /run/systemd/system/-.mount.
Removed /run/systemd/system/media-tester-966d0a59\x2d9e02\x2d45d8\x2d8d27\x2d6916fdf9a4ee.mount.
Removed /run/systemd/system/run-user-1000.mount.
Removed /run/systemd/system/run-user-120.mount.
Removed /run/systemd/system/tmp.mount.
tester@tester-SATELLITE-PRO-C850-19W:~$ gksudo xterm
Error copying '/home/tester/.Xauthority' to '/tmp/libgksu-GQiFHn': No such file or directorytester@tester-SATELLITE-PRO-C850-19W:~$
tester@tester-SATELLITE-PRO-C850-19W:~$ gksudo nautilus
Error copying '/home/tester/.Xauthority' to '/tmp/libgksu-gFaMxY': No such file or directorytester@tester-SATELLITE-PRO-C850-19W:~$
tester@tester-SATELLITE-PRO-C850-19W:~$ gksudo gparted
Error copying '/home/tester/.Xauthority' to '/tmp/libgksu-rkGkLW': No such file or directorytester@tester-SATELLITE-PRO-C850-19W:~$
-----

The corresponding commands work in a live system, which is not running on Wayland. So I suspect that this bug is due to Wayland.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: xwayland 2:1.19.3-1ubuntu2
ProcVersionSignature: Ubuntu 4.11.0-10.15-generic 4.11.8
Uname: Linux 4.11.0-10-generic x86_64
ApportVersion: 2.20.6-0ubuntu4
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: GNOME
Date: Mon Jul 24 20:26:54 2017
DistUpgraded: Fresh install
DistroCodename: artful
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Toshiba America Info Systems 3rd Gen Core processor Graphics Controller [1179:fb31]
InstallationDate: Installed on 2017-07-17 (6 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Alpha amd64 (20170716)
MachineType: TOSHIBA SATELLITE PRO C850-19W
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.11.0-10-generic root=UUID=00d61d20-2d13-4b1b-8c01-7c23cc38fc57 ro quiet splash vt.handoff=7
SourcePackage: xorg-server
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 09/24/2012
dmi.bios.vendor: Insyde Corp.
dmi.bios.version: 6.10
dmi.board.asset.tag: Type2 - Board Asset Tag
dmi.board.name: PLCSF8
dmi.board.vendor: Intel
dmi.board.version: Type2 - Board Version
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: OEM Chassis Manufacturer
dmi.chassis.version: OEM Chassis Version
dmi.modalias: dmi:bvnInsydeCorp.:bvr6.10:bd09/24/2012:svnTOSHIBA:pnSATELLITEPROC850-19W:pvrPSCBXE-00C00VN5:rvnIntel:rnPLCSF8:rvrType2-BoardVersion:cvnOEMChassisManufacturer:ct10:cvrOEMChassisVersion:
dmi.product.name: SATELLITE PRO C850-19W
dmi.product.version: PSCBXE-00C00VN5
dmi.sys.vendor: TOSHIBA
version.compiz: compiz N/A
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.81-2
version.libgl1-mesa-dri: libgl1-mesa-dri 17.1.2-2ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 17.1.2-2ubuntu2
version.xserver-xorg-core: xserver-xorg-core 2:1.19.3-1ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.9.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20170309-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2