hp-systray is visible, but not clickable with the mouse

I have a hp-photsmart C4580. I set up this printer with hp-setup and the printer and scanner work.
But the hp-systray is visible, but not clickable with the mouse.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: hplip-gui 3.17.10+repack0-5
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Uname: Linux 4.15.0-20-generic x86_64
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CupsErrorLog:
 E [10/May/2018:11:01:25 +0200] [cups-deviced] PID 2235 (gutenprint52+usb) stopped with status 1!
 E [10/May/2018:11:06:11 +0200] [Client 35] Local authentication certificate not found.
CurrentDesktop: ubuntu:GNOME
Date: Thu May 10 18:31:49 2018
InstallationDate: Installed on 2018-05-05 (5 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180425.1)
Lpstat: device for Photosmart_C4500: hp:/net/Photosmart_C4500_series?ip=192.168.0.10
MachineType: Acer Aspire V3-771
PackageArchitecture: all
Papersize: a4
PpdFiles: Error: command ['fgrep', '-H', '*NickName', '/etc/cups/ppd/Photosmart_C4500.ppd'] failed with exit code 2: grep: /etc/cups/ppd/Photosmart_C4500.ppd: Permission denied
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-20-generic root=UUID=0ac5e129-9862-49f6-a0ae-dff644abfb33 ro quiet splash vt.handoff=1
SourcePackage: hplip
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 03/06/2013
dmi.bios.vendor: Insyde Corp.
dmi.bios.version: V1.15
dmi.board.asset.tag: Type2 - Board Asset Tag
dmi.board.name: VA70_HC
dmi.board.vendor: Type2 - Board Vendor Name1
dmi.board.version: Type2 - Board Version
dmi.chassis.type: 10
dmi.chassis.vendor: Chassis Manufacturer
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnInsydeCorp.:bvrV1.15:bd03/06/2013:svnAcer:pnAspireV3-771:pvrV1.15:rvnType2-BoardVendorName1:rnVA70_HC:rvrType2-BoardVersion:cvnChassisManufacturer:ct10:cvrChassisVersion:
dmi.product.family: Type1Family
dmi.product.name: Aspire V3-771
dmi.product.version: V1.15
dmi.sys.vendor: Acer