perhaps the simplest way to install famistudio on gnu/linux: (tried on ubuntu, using flatpak - might take 1gb of hd space... :S ):
- in the terminal, enter "sudo apt install flatpak"
- at https://flathub.org/apps/org.famistudio.FamiStudio click on "install" button - it downloads org.famistudio.FamiStudio.flatpakref file
- in the terminal again, in the directory where org.famistudio.FamiStudio.flatpakref is, enter "flatpak install org.famistudio.FamiStudio.flatpakref"
- and then, enter "flatpak run org.famistudio.FamiStudio" for running it

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