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Technically this is more of a program with different skeuomorphic themes than a single theme. But I thought I'd let people know about it because it looks cool & there's not a lot on customization for MacOS. I think it should be included under "useful software" on the resources page.
Here's the link. In Linux Mint, it can found in the software manager by looking up "cool retro term". I'm not sure about other distros though. However there are build instructions for both MacOS & different Linux distros at the bottom. There's also a dmg file under the releases.
