It’s quite a hefty app at nearly 900 MB, but once started up runs a lot quicker than most Macs of the day. Although its author describes it as a “toy”, he does himself a disservice. If you have the slightest interest in the history of the Mac, or in human interface design, it’s completely compelling. It comes pre-loaded with a bunch of game demos, including Oregon Trail, Duke Nukem 3D and Civilization II, but sadly not Crystal Quest. There are also several tryout versions of Adobe apps like Photoshop 3, Illustrator 5.5, and Streamline 3.1.
If you’ve got compatible Classic apps available in Stuffit archives, you can transfer those across using a shared folder too. Trying this with uncompressed apps wasn’t successful, though, because macintosh.js didn’t recognise their modernised and flattened format.
I’m off now to find some suitably Stuffited copies of some of my old apps. I may be some time.
macintosh.js is properly signed and notarized for modern releases of macOS, and runs a treat in Catalina. It’s available from here. Thank you, Felix and friends: I have at last found an Electron app which is outstanding.