WebApp crashes with Ubuntu 16.04 (modules not installed, Uncaught ReferenceError)

1) The release of Ubuntu I am using, via 'lsb_release -rd'

$ lsb_release -rd
Description: Ubuntu 16.04 LTS
Release: 16.04

2) the package I am using via 'apt-cache policy pkgname'

$ apt-cache policy unity-webapps-twitter
unity-webapps-twitter:
  Installed: 2.4.16+16.04.20151119-0ubuntu1
  Candidate: 2.4.16+16.04.20151119-0ubuntu1
  Version table:
 *** 2.4.16+16.04.20151119-0ubuntu1 500
        500 http://de.archive.ubuntu.com/ubuntu xenial/universe amd64 Packages
        500 http://de.archive.ubuntu.com/ubuntu xenial/universe i386 Packages
        100 /var/lib/dpkg/status

3) What I expected to happen

I have been using the WebApp with Ubuntu 14.04 for the last years. Now I am migrating to Ubuntu 16.04 and I expected to run WebApp for Twitter as I used to with Ubuntu 14.04.3

I usually execute /usr/share/applications/Twitter.desktop

[Desktop Entry]
Name=Twitter
Type=Application
Icon=unity-webapps-twitter
MimeType=
Actions=S0;S1;S2;S3;S4;S5;S6;S7;S8;S9;S10;
Exec=unity-webapps-runner -n 'VHdpdHRlcg==' -d 'twitter.com' %u
StartupWMClass=Twittertwittercom

4) What happened instead

I found the WebApp unfeasible. This is the result of executing “unity-webapps-runner -n 'VHdpdHRlcg==' -d 'twitter.com' %u” in a GNOME terminal

user@box3:~$ unity-webapps-runner -n 'VHdpdHRlcg==' -d 'twitter.com' %u
** Message: Launching webapp 'Twitter' with the webapp container (command line 'webapp-container --app-id='Twittertwittercom' --webapp='VHdpdHRlcg==' --enable-back-forward ')
user@box3:~$ Invalid webapp webapp definition: homepage not found or fails predicate isString
Could not open manifest file: "/usr/share/unity-webapps/userscripts/unity-webapps-amazon/manifest.json"
qml: Loading webview on /home/user/.local/share/Twittertwittercom
Invalid webapp webapp definition: homepage not found or fails predicate isString
Could not open manifest file: "/usr/share/unity-webapps/userscripts/unity-webapps-amazon/manifest.json"
QQmlExpression: Expression file:///usr/share/webbrowser-app/webcontainer/WebApp.qml:272:25 depends on non-NOTIFYable properties:
    unity::action::qml::ActionManager::globalContext
qml: Loaded 5 UA override(s) from file:///usr/lib/x86_64-linux-gnu/qt5/qml/Ubuntu/Web/ua-overrides-mobile.js
qml: Start browsing
qml: Could not create ContentHub backend (does not appear to be installed)
qml: Requesting the bindee to navigate to homepage: https://twitter.com/
file:///usr/share/webbrowser-app/webcontainer/ContentPickerDialog.qml:22:1: module "Ubuntu.Content" is not installed
file:///usr/share/webbrowser-app/webcontainer/ContentDownloadDialog.qml:22:1: module "Ubuntu.Content" is not installed
file:///usr/share/webbrowser-app/ContentHandler.qml:20:1: module "Ubuntu.Content" is not installed
file:///usr/share/webbrowser-app/Downloader.qml:22:1: module "Ubuntu.DownloadManager" is not installed
file:///usr/share/webbrowser-app/Downloader.qml:23:1: module "Ubuntu.Content" is not installed
file:///usr/share/webbrowser-app/Downloader.qml:22:1: module "Ubuntu.DownloadManager" is not installed
file:///usr/share/webbrowser-app/Downloader.qml:23:1: module "Ubuntu.Content" is not installed
qml: Loaded 5 UA override(s) from file:///usr/lib/x86_64-linux-gnu/qt5/qml/Ubuntu/Web/ua-overrides-desktop.js
[0701/124123:ERROR:layer_tree_host_impl.cc(2206)] Forcing zero-copy tile initialization as worker context is missing
[0701/124125:ERROR:oxide_user_script_slave.cc(168)] Caught exception when calling script: Uncaught ReferenceError: external is not defined
[0701/124125:ERROR:oxide_user_script_slave.cc(168)] Caught exception when calling script: Uncaught ReferenceError: external is not defined
[0701/124125:ERROR:oxide_user_script_slave.cc(168)] Caught exception when calling script: Uncaught ReferenceError: external is not defined
[0701/124125:ERROR:oxide_user_script_slave.cc(168)] Caught exception when calling script: Uncaught ReferenceError: external is not defined
[0701/124125:ERROR:oxide_user_script_slave.cc(168)] Caught exception when calling script: Uncaught ReferenceError: external is not defined
[0701/124125:ERROR:oxide_user_script_slave.cc(168)] Caught exception when calling script: Uncaught ReferenceError: external is not defined
[0701/124125:ERROR:oxide_user_script_slave.cc(168)] Caught exception when calling script: Uncaught ReferenceError: external is not defined
[0701/124125:ERROR:oxide_user_script_slave.cc(168)] Caught exception when calling script: Uncaught ReferenceError: external is not defined
OxideQQuickScriptMessage: args is deprecated. Please use payload instead
qml: WebApps API message being dispatch: init
^C
user@box3:~$ ^C

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: unity-webapps-twitter 2.4.16+16.04.20151119-0ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-28.47-generic 4.4.13
Uname: Linux 4.4.0-28-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: Unity
Date: Fri Jul 1 15:10:27 2016
EcryptfsInUse: Yes
InstallationDate: Installed on 2016-06-22 (8 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
PackageArchitecture: all
SourcePackage: unity-webapps-twitter
UpgradeStatus: No upgrade log present (probably fresh install)