I wrote this description somewhere early in 2000 and hardly updated it since that time.
Hotjava 3 has never really become a mainstream browser. After having detected browsers for many years, I found only 10 or so Hotjava hits on the sites I'm monitoring. I included it for fun.
One very irritating feature of Hotjava is that when you hit 'Reload', it opens a new window with the old site, without your changes. It is generally nearly impossible to make Hotjava reload anything.
One very strange feature of Hotjava is that it supports document.layers, the DOM also supported by Netscape 4. This is the more strange since it doesn't actually seems to do anything with the DOMand that it always complains that it cannot find document.all . Since I always write my scripts to ensure that a document.layers capable browser only executes the document.layers bit of the script, I don't understand why Hotjava tries to execute the document.all bits.
As to the Mac version: it's horrible. First of all it starts up a kind of Java window and the browser inside this window, which means that you have two sets of scrollbars: one for the Java window and one for the browser. Furthermore, it crashes with disturbing regularity. Not recommended.