Z axis coordinates not updating dynamically

[ubiquity]

OK - thanks for the explanation!
I shall point this out to my students as an anomaly, rather than a bug, since, at present, I can see no practical purpose for the dynamic figures.

P.S. It would make an interesting mathematical problem, for those so inclined, to resolve the 2D space coordinates shown dynamically into t .he 3D space positional coordinates or vice-versa