Basic examples not working / working erratically

[robwold]

Trying to run the basic examples from http://nbviewer.jupyter.org/github/domitry/nyaplot/blob/master/examples/notebook/Getting_Started_with_Nyaplot.ipynb
in a jupyter notebook with ruby 2.4.0, I got a grey screen. At first, it worked with the Daru/view wrapper, but then mysteriously stopped working when I left the notebook and returned. I don't see any evidence of it being related to the HTTP(S) issue from domitry/nyaplot- if it is could it depend on the websocket port?

I've tried in both Chrome and Safari.