Jochen (who's website you linked) is the lead author of the paper. The line under the byline reads:

> This article was presented at VISxAI, it is now under review at distill.pub.

An earlier version of this paper was presented at the VisxAI workshop, and then later expanded into a journal paper published in Distill.

(Disclosure: I'm one of Distill's editors, but was not involved in editing this particular paper.)