Make your XFCE desktop look as close as possible to an old IRIX machine.
SGI Screen Fonts
https://www.gnome-look.org/p/998527/
Xfwm4 theme that is based on the window manager for SGI OS.
https://www.gnome-look.org/p/1015906/
SGI-IMD Metacity theme. This also works with MATE.
https://www.gnome-look.org/p/1006689/
SGI Irix cursor theme. This works with any window manager.
https://www.gnome-look.org/p/999497/
SGI IRIX icons theme.
https://github.com/n-kremeris/irix-icons-linux
This whole thing brought together, would make a Xfce4 desktop look just like an old IRIX workstation. or as close as possible. A nice IRIX themed XFCE. Files linked above. For the fonts you need to be sure to run dpkg-reconfigure fontconfig-config
as sudo or root on Debian based systems. Then you can enable bitmapped fonts. Otherwise the SGI fonts look blurry. This is well worth setting up on your machine if the current look is not to your taste and it is desired to have a retro look.
This Fedora 26 RPM file also has some nice themes in it. The same ones linked above in one package.
https://fedora.pkgs.org/26/rpm-sphere/sgi-theme-2016-13.1.noarch.rpm.html.
Just open it with an archive manager and extract the files for use on any Linux system.
Above is my MATE desktop with SGI theme elements installed. This looks very good, I just need to add the bitmap fonts, and it will be complete.
You forgot about the close button.