There's absolutely nothing complex about the layout in that Cubase screenshot. It's likely mostly (if not fully) manually positioned which you can do with CSS.

There's absolutely nothing complex about the layout in that Cubase screenshot. It's likely mostly (if not fully) manually positioned which you can do with CSS. The rendering is more complex because a lot of it would need to be represented as images/SVGs to render all those lines at least somewhat efficiently. The thread you linked kind of touches on that, too, by pointing out that sometimes you need to drop down to handling layout+rendering yourself. Doesn't matter if it's a desktop or web app. It is actually the best option to do sometimes because it can be less hacky and more performant.