gnome-software spams syslog with assertion errors: json_object_has_member: assertion 'member_name != NULL' failed | g_strsplit: assertion 'string != NULL' failed | g_strv_length: assertion 'str_array != NULL' failed

The fan and cpu is very active during this event, thousands of assertions reported. Syslog case attached.

lsb_release -rd
Description: Ubuntu 18.04.1 LTS
Release: 18.04

apt-cache policy gnome-software
gnome-software:
  Installed: 3.28.1-0ubuntu4.18.04.3
  Candidate: 3.28.1-0ubuntu4.18.04.3
  Version table:
 *** 3.28.1-0ubuntu4.18.04.3 500
        500 http://ftp.acc.umu.se/ubuntu bionic-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     3.28.1-0ubuntu4 500
        500 http://ftp.acc.umu.se/ubuntu bionic/main amd64 Package

apt-cache policy gnome-shell
gnome-shell:
  Installed: 3.28.3-0ubuntu0.18.04.2
  Candidate: 3.28.3-0ubuntu0.18.04.2
  Version table:
 *** 3.28.3-0ubuntu0.18.04.2 500
        500 http://ftp.acc.umu.se/ubuntu bionic-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     3.28.1-0ubuntu2 500
        500 http://ftp.acc.umu.se/ubuntu bionic/main amd64 Packages

uname -a
Linux computer 4.15.0-34-generic #37-Ubuntu SMP Mon Aug 27 15:21:48 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

gnome-shell --version
GNOME Shell 3.28.3

Sep 29 06:58:01 computer gnome-software[2694]: json_object_has_member: assertion 'member_name != NULL' failed
Sep 29 06:58:01 computer gnome-software[2694]: g_strsplit: assertion 'string != NULL' failed
Sep 29 06:58:01 computer gnome-software[2694]: g_strv_length: assertion 'str_array != NULL' failed
Sep 29 06:58:01 computer gnome-software[2694]: json_object_has_member: assertion 'member_name != NULL' failed
Sep 29 06:58:01 computer gnome-software[2694]: g_strsplit: assertion 'string != NULL' failed
Sep 29 06:58:01 computer gnome-software[2694]: g_strv_length: assertion 'str_array != NULL' failed
Sep 29 06:58:01 computer gnome-software[2694]: json_object_has_member: assertion 'member_name != NULL' failed
Sep 29 06:58:01 computer gnome-software[2694]: g_strsplit: assertion 'string != NULL' failed
---
ProblemType: Bug
ApportVersion: 2.20.9-0ubuntu7.4
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
DisplayManager: gdm3
DistroRelease: Ubuntu 18.04
InstallationDate: Installed on 2015-07-18 (1168 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
Package: gnome-shell 3.28.3-0ubuntu0.18.04.2
PackageArchitecture: amd64
ProcVersionSignature: Ubuntu 4.15.0-34.37-generic 4.15.18
Tags: bionic third-party-packages
Uname: Linux 4.15.0-34-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip libvirt libvirtd lpadmin plugdev sambashare sudo
_MarkForUpload: True