Error when trying to create review for gnome extension

[CrazySky]

I have a error when trying to create review for any gnome extension software.

For example, Redmine issues.

Test Case:

1) Open redmine issues extension in gnome software and login into Ubuntu account
2) Press a button for writing a review
3) Set rating, write theme and review and try to post you review
4) You will get an error "Got unknown content type text/html from reviews.ubuntu.com"

------------

1) Ubuntu 17.10
2) 3.26.1-0ubuntu2
3) Review must sended successfully
4) Got an error Got unknown content type text/html from reviews.ubuntu.com"

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: gnome-software 3.26.1-0ubuntu2
ProcVersionSignature: Ubuntu 4.13.0-17.20-generic 4.13.8
Uname: Linux 4.13.0-17-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.7-0ubuntu3.5
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Mon Nov 27 07:18:58 2017
ExecutablePath: /usr/bin/gnome-software
InstallationDate: Installed on 2017-05-11 (200 days ago)
InstallationMedia: Ubuntu 16.04.2 LTS "Xenial Xerus" - Release amd64 (20170215.2)
InstalledPlugins:
 gnome-software-plugin-flatpak N/A
 gnome-software-plugin-limba N/A
 gnome-software-plugin-snap 3.26.1-0ubuntu2
SourcePackage: gnome-software
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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

[Sebastien Bacher (seb128)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. The issue you are reporting is an upstream one and it would be nice if somebody having it could send the bug to the developers of the software by following the instructions at https://wiki.ubuntu.com/Bugs/Upstream/GNOME. If you have done so, please tell us the number of the upstream bug (or the link), so we can add a bugwatch that will inform us about its status. Thanks in advance.