https://askubuntu.com/questions/913892/how-to-install-scratch-2-on-ubuntu-16-10-or-17-04-64bit/913912
# install necesary i386 libraries
$ sudo apt-get install libgtk2.0-0:i386 libstdc++6:i386 libxml2:i386 libxslt1.1:i386 libcanberra-gtk-module:i386 gtk2-engines-murrine:i386 libqt4-qt3support:i386 libgnome-keyring0:i386 libnss-mdns:i386 libnss3:i386
# make keyring visible for Adobe Air
$ sudo ln -s /usr/lib/i386-linux-gnu/libgnome-keyring.so.0 /usr/lib/libgnome-keyring.so.0
$ sudo ln -s /usr/lib/i386-linux-gnu/libgnome-keyring.so.0.2.0 /usr/lib/libgnome-keyring.so.0.2.0
# Download Adobe Air
cd ~/Downloads
wget http://airdownload.adobe.com/air/lin/download/2.6/AdobeAIRSDK.tbz2
$ sudo mkdir /opt/adobe-air-sdk
$ sudo tar jxf AdobeAIRSDK.tbz2 -C /opt/adobe-air-sdk
# Download Air runtime/SDK from Archlinux
wget https://aur.archlinux.org/cgit/aur.git/snapshot/adobe-air.tar.gz
$ sudo tar xvf adobe-air.tar.gz -C /opt/adobe-air-sdk
$ sudo chmod +x /opt/adobe-air-sdk/adobe-air/adobe-air
# Get actual scratch file URL from https://scratch.mit.edu/scratch2download/
$ sudo mkdir /opt/adobe-air-sdk/scratch
wget https://scratch.mit.edu/scratchr2/static/sa/Scratch-456.0.1.air
$ sudo cp Scratch-456.0.1.air /opt/adobe-air-sdk/scratch/
cp Scratch-456.0.1.air /tmp/
cd /tmp/
unzip /tmp/Scratch-456.0.1.air
$ sudo cp /tmp/icons/AppIcon128.png /opt/adobe-air-sdk/scratch/scratch.png
Create launcher:
$ cat << _EOF_ > /usr/share/applications/Scratch2.desktop
[Desktop Entry]
Encoding=UTF-8
Version=1.0
Type=Application
Exec=/opt/adobe-air-sdk/adobe-air/adobe-air /opt/adobe-air-sdk/scratch/Scratch-456.0.1.air
Icon=/opt/adobe-air-sdk/scratch/scratch.png
Terminal=false
Name=Scratch 2
Comment=Programming system and content development tool
Categories=Application;Education;Development;ComputerScience;
MimeType=application/x-scratch-project
_EOF_
$ chmod +x /usr/share/applications/Scratch2.desktop