A bit OT: What's up with the mouse pointer on that page? Why on earth would a site that has "design" in it's domain name change my mouse pointer to a finger-sized circle blob on my 4K desktop screen?

Like the other commenter, my mind also fixated on the mouse cursor. Great post on the fonts, but I spent most of my time seeing how the strange cursor behaved. I don't like it much, especially because there's some inconsistency once you're down hovering over the related posts.

However, there was one spot where I had to give it to them: when I hovered over the content about Google Sans Code, it expanded horizontally. For a second, I wondered what was going on, then it clicked that the content must be horizontally scrollable, which it was!

Of course, that could be shown with a much more obvious horizontal scroll bar...

I never saw the cursor changing size to fit the button you are hovering on, it's pretty cool, I don't know if it's better but it's cool.

This is a great case study in need-driven design. I especially like how every iteration of Google Sans came from a concrete usability failure—legibility, scale, language support, or developer ergonomics—rather than aesthetics alone. Open-sourcing Flex feels like a natural extension of that philosophy, not just a branding move.