And all the code pens are also slow. Between clicking the "run" button and the actual script running there's somewhat of a 3 second gap.
Which kind of puts the opening paragraph into question:
> I’m passionate about image performance optimisation and making images load fast on the web.
Like, ok, why aren't you using a simpler blog engine to post? As a plus, if you were in control of everything on the page, you wouldn't even need to use codepen; just include the javascript directly in your page.