Comment 4 for bug 1683355

For everyone interested - I made it working:

See comment on [bug 1683516](https://bugs.launchpad.net/ubuntu/+source/indicator-applet/+bug/1683516/comments/5).

You can do the following:

    sudo apt-get install libindicate-gtk3 libindicate5 python-indicate python-gnomekeyring python-notify

    cd ~/Downloads
    wget http://archive.ubuntu.com/ubuntu/pool/universe/p/python-support/python-support_1.0.14ubuntu2_all.deb
    sudo dpkg -i python-support_1.0.14ubuntu2_all.deb

    wget http://ppa.launchpad.net/ralf.hersel/rhersel-ppa/ubuntu/pool/main/p/popper/popper_0.31.3-0ubuntu1_all.deb
    sudo dpkg -i popper_0.31.3-0ubuntu1_all.deb

    wget http://archive.ubuntu.com/ubuntu/pool/main/i/indicator-messages/libindicator-messages-status-provider1_0.6.0-0ubuntu2_`dpkg --print-architecture`.deb
    sudo dpkg -i libindicator-messages-status-provider1_0.6.0-0ubuntu2_`dpkg --print-architecture`.deb

    wget http://archive.ubuntu.com/ubuntu/pool/main/i/indicator-messages/indicator-messages_0.6.0-0ubuntu2_`dpkg --print-architecture`.deb
    sudo dpkg -i indicator-messages_0.6.0-0ubuntu2_`dpkg --print-architecture`.deb

    wget http://archive.ubuntu.com/ubuntu/pool/universe/i/indicator-messages/indicator-messages-gtk2_0.6.0-0ubuntu2_`dpkg --print-architecture`.deb
    sudo dpkg -i indicator-messages-gtk2_0.6.0-0ubuntu2_`dpkg --print-architecture`.deb

Then `mate-tweak` *-> Panel (Interface) -> Enable indicators*.

Then *Applications -> Internet -> Popper*

    cat <<EOF | sudo tee /etc/apt/preferences.d/pin-indicators
    Package: indicator-messages
    Pin: version 0.6.0-0ubuntu2
    Pin-Priority: 1337

    Package: indicator-messages-gtk2
    Pin: version 0.6.0-0ubuntu2
    Pin-Priority: 1337

    Package: libindicator-messages-status-provider1
    Pin: version 0.6.0-0ubuntu2
    Pin-Priority: 1337

    Package: popper
    Pin: version 0.31.3-0ubuntu1
    Pin-Priority: 1337

    Package: python-support
    Pin: version 1.0.14ubuntu2
    Pin-Priority: 1337

    EOF

Posted solution on the AskUbuntu - see https://askubuntu.com/a/965156/66509 .