Firestorm Viewer install for linux Mint

First update your environment:

Open a terminal and type the following:
sudo apt update; sudo apt upgrade; sudo apt autoremove

Then Download Firestorm from their web site.

https://www.firestormviewer.org/choose-your-platform/

Pick the Penguin, and the 64 bit download.

Extract the file by either
tar -xvf Phoenix-Firestorm-Releasex64-6-6-8-68380.tar.xz
or with the file viewer using Archive Manager.

Now install. I install to  /opt/fire/  the default is /opt/firestorm/ anyplace in opt is fine.
Open a terminal again.
cd Phoe*68380
sudo ./install.sh

If you would prefer native linux SL Voice, you will likely need to install a couple of i386 library files  (32 bit type).

sudo apt-get install gstreamer1.0-pulseaudio:i386 libidn12:i386 libuuid1:i386 libstdc++6:i386

You will also need to create a symbolic link from libidn12 to libidn11 in your /lib/i386-linux-gnu directory.

cd /lib/i386-linux-gnu

sudo ln -s libidn.so.12 libidn.so.11

You will not need to add these files or recreate the symbolic link for subsequent installs of firestorm.

Firestorm should now run with linux native SLVoice support.