Accidental stacking comparison tool gone?

I wanted to revisit the entry on accidantal handling in the making notes blog.

However, I tried to use the accidental stacking comparison tool with 3 different web browsers and it seems to work in none of them.

Has this been removed deliberately or is something broken?

This was broken when the blog was moved from blog.steinberg.net to the new site at dorico.com.

Here’s an archived version that still works: