DHTML in Netscape 4 was also completely incompatible with DHTML in IE 4. In IE you had the DOM, which is an inconvenient and inherently very inefficient interface that you could coerce into doing anything you wanted. In Netscape 4 you had layers. Our team (KnowNow) was working on an AJAX and Comet toolkit at the time (02000). In order to not write separate versions of our Comet applications for the two browsers, we stuck to the least common denominator, which was basically framesets and document.write.
https://en.wikipedia.org/wiki/Netscape_Navigator#:~:text=Thi...
Netscape 4 is a broad set of releases over several years. It also wasn't necessarily "bad". It was just largely not mindblowingly better than Netscape 3 (for normal users) while using more CPU and RAM.
I also imagine in this context it's incomplete CSS support is problematic. Netscape 3 will ignore properly commented out CSS (mostly) while 4 will try to interpret what it can and choke on the rest. It's box model doesn't conform to where the CSS spec landed so even if you can give it CSS it can handle, your page is broken in every other browser.
At the end, there was something like acceptable variation in page view for different browsers.
Thanks. Learning web development back then left some deep scars and lasting lessons. I can no longer imagine all the other stuff I haven't retained because I remember stupid browser quirks from nearly three decades ago.
Getting many designs working consistently between IE and Netscape was impossible. The 640px wide left-aligned table layout was popular for years because it was the easiest common denominator that looked acceptable in both browsers.
Take for example VRML, particularly VRML 2.0. I don't remember the software name, but there was a chat system within a virtual world, perhaps running in a browser (1).
1. https://csdl-images.ieeecomputer.org/mags/cg/1999/02/figures...
But I also don't think 3 was much better.
http://macpaint.org
(From page HTML source) <!-- ******** HELLO OLD COMPUTER USERS ******** --> <!-- This site is designed to be viewable at 640x480 resolution or higher in any color mode in Netscape/IE 3 or any better browser, so if you're using an LC III or something, you're welcome. In fact, I really hope you are using such a machine, because limiting the site to this level of simplicity wouldn't be worth it unless someone is. Please let me know if you are using an old computer to visit the site so I know it is worth it to someone to maintain this compatibility. I do apologize for the one javascript error that you may get on each page load, but I don't expect it to cause any crashes. The major exception to all of this is Netscape 4. That thing sucks. -->
Does anyone even remember why Netscape 4 was bad?