In typical fashion, after posting I've now resolved this issue with some more searching.
I had tried removing the following registerPlugin line altogether:
gsap.registerPlugin(Draggable);
But that gave another error:
TypeError: _toArray is not a function
So I knew this was needed.
It turns out that adding a condition to check for the window object around this line solves the issue.
The following now works fine:
import { gsap } from 'gsap';
import { Draggable } from 'gsap/dist/Draggable';
if (typeof window !== 'undefined') {
gsap.registerPlugin(Draggable);
}
