Links of the form https://threejs.org/build/three.js
are also problematic, because the content changes with the versions.
An older example:
I noticed that there is a problem, when I was looking at the examples from discourse.threejs.org
The solution @prisoner849
Edit fiddle - JSFiddle - Code Playground uses threejs.org/build/three.min.js
Therefore I have always tried to use the currently valid version in the examples. In addition the version number in the file name.