Some seems to be server-side (LiveWire), as well, which was a Netscape product long before Node.js, but I'm not sure if this was already available, then. (When was the Netscape Enterprise server launched?)

I'm also not too sure, if LiveConnect (the connection between JS and Java applets and vice versa) was already a thing, when JavaScript was announced. (I think, this came a little later.)

Edit: I've a Netscape JavaScript book from when this was still in beta. (My first reading on the subject.) It does mention applets on a single page and that you may address them per ID via LiveConnect in a single sentence. So this was already implemented, but it wasn't advertised prominently. The book is all about form based examples.

(The applications in this book were the same that were demoed as showcase applications by Netscape on their website – and probably represent a significant part of what these voices reacted to.)

My memory is that around '98 people were falling over themselves to figure out how to wire up "components" made of applets. I think that stopped being a thing when people figured out SpyGlass/IE didn't use the same techniques to wire applets as Netscape. So props to you Microsoft, you made my life irritating for multiple decades (don't get me started about 1990 when I was a beta tester for Microsoft C 5.0.)

I remember using Netscape Enterprise Server suite, but didn't realize it had a JS engine in it. I do remember Rhino from a little later (though the wikipedia says it emerged in the late 90s.) And I have relatively horrible memories of the Netscape guys integrating the Visigenic ORB in both the enterprise server and Navigator. I wonder if Rhino was what they stuffed into NES/iPlanet/Sun ONE.