Para instalar o Kompozer, pressione Ctrl + Alt + T no seu teclado para abrir o Terminal. Quando se abre, execute o (s) comando (s) abaixo:
sudo apt-get install libatk1.0-0 libc6 libcairo2 libfontconfig1 libfreetype6 libgdk-pixbuf2.0-0 libglib2.0-0 libgtk2.0-0 libidl0 libnspr4 libnss3 libpango1.0-0 libpng12-0 libstdc++6 libx11-6 libxft2 libxinerama1 libxrender1 libxt6 zlib1g
Para sistemas de 32 bits:
wget -c https://launchpad.net/ubuntu/+archive/primary/+files/kompozer-data_0.8~b3.dfsg.1-0.1ubuntu2_all.deb
wget -c https://launchpad.net/ubuntu/+archive/primary/+files/kompozer-dev_0.8~b3.dfsg.1-0.1ubuntu2_all.deb
wget -c https://launchpad.net/ubuntu/+archive/primary/+files/kompozer_0.8~b3.dfsg.1-0.1ubuntu2_i386.deb
Então faça:
sudo dpkg -i kompozer*.deb
sudo apt-get install -f
Para sistemas de 64 bits:
wget -c https://launchpad.net/ubuntu/+archive/primary/+files/kompozer-data_0.8~b3.dfsg.1-0.1ubuntu2_all.deb
wget -c https://launchpad.net/ubuntu/+archive/primary/+files/kompozer-dev_0.8~b3.dfsg.1-0.1ubuntu2_all.deb
wget -c https://launchpad.net/ubuntu/+archive/primary/+files/kompozer_0.8~b3.dfsg.1-0.1ubuntu2_amd64.deb
Então faça:
sudo dpkg -i kompozer*.deb
sudo apt-get install -f
Fonte: Instale o Kompozer