I must be missing something, because isn't 3 images side by side just:
<div><img ...><img ...><img ...></div>
? But you're right, the web isn't a UI platform. It's designed for to produce things that are like Microsoft Word documents. Web-apps are like using MSWord's scripting and text layout to produce a MSWord-app. Yeah, one can do it, but it's like cutting a steak with a spoon.
You are somewhat correct. I just tested with the tiny HN logo (upper left of this page), and a div with 3 imgs makes them appear side-by-side. The issue I had previously was that the three images were quite wide, and while I wanted them to still go next to each other (with a horizontal scrollbar in the browser), the browser moved images into a new row if they would overflow past the right edge.
I haven't used JavaFX in a while but I'd bet there's a checkbox you can toggle in the builder GUI to control how an HBox overflows.
The solution for HTML/CSS was to give the outer div "white-space: nowrap" and the three inner divs (with images inside them) "display: inline-block".
<div><img ...><img ...><img ...></div>
? But you're right, the web isn't a UI platform. It's designed for to produce things that are like Microsoft Word documents. Web-apps are like using MSWord's scripting and text layout to produce a MSWord-app. Yeah, one can do it, but it's like cutting a steak with a spoon.