Ask HN: Does Waze “Arrive at” work for you in Firefox?

I noticed that, after choosing the endpoints of a trip, if I try to choose an arrival time in Firefox, the page blanks out except for a loading animation in the center. If I do the same in Chrome, it looks like it's working. Can you reproduce this? Is it an example of Google's anti-competitive practices, since they own the browser and Waze as well?