Highlighting multiple hex_tiles by hovering

A few weeks ago I used the accepted answer from this post on Stack Overflow as the basis for my own visualization, which also highlights all circles belonging to the same class when hovering over anyone of the circles in said class. Everything worked perfectly until about a week ago when suddenly this effect didn’t work anymore, neither in my own visualization nor in the one from the post.

I haven’t changed anything in my own setup, therefore my question is twofold:

1. What caused this change?
2. How do I modify the accepted answer from the Stack Overflow post to achieve the same effect again?

Try the code from python - Highlighting multiple hex_tiles by hovering in bokeh - Stack Overflow again - I’ve fixed it. Likely, it has stopped working for you because you updated Bokeh to a newer version that uses the strict mode for JS by default.

You are absolutely right. I had no idea about strict mode, I’m learning. Thanks you so much, Eugene!