Synaptic cannot be started from the GNOME shell

[Alexander Kallenbach]

As described above. Nothing happens when I try to open it from the gnome shell. I can only open it from the terminal.

ProblemType: Bug
DistroRelease: Ubuntu 18.10
Package: synaptic 0.84.4
ProcVersionSignature: Ubuntu 4.18.0-12.13-generic 4.18.17
Uname: Linux 4.18.0-12-generic x86_64
ApportVersion: 2.20.10-0ubuntu13.1
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Thu Dec 13 22:46:54 2018
InstallationDate: Installed on 2018-11-30 (13 days ago)
InstallationMedia: Ubuntu 18.10 "Cosmic Cuttlefish" - Release amd64 (20181017.3)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: synaptic
UpgradeStatus: No upgrade log present (probably fresh install)