"Then the client was clunky and slow, nothing else on the web felt as slow even with such little graphical sparkle. It was basically a side-by-side email client by look, yet acted like it was folding proteins or mining bitcoin in some worker thread."
IIR it all written in Java then compiled to Javascript, I think using an old version of GWT. I was not a good showpiece for the technology. It was like stepping back in time to the early Java days with a pre-JIT JVM and slow computers.
It seemed to be a heavy user of memory iirc?