Gadfly plot - zoom does not work

Plotting with Gadfly, the zoom option does not work. Panning works perfectly both with the mouse (trackpad in this case) and with the H,J,K,L keys. But zooming does not work not with the mouse, and not with the +,- keys.
I’m running on Mac 10.14.4, on Jupyter notebook.

I just realized that this is a Firefox issue. It works great on Safari.

Relevant issue here. It’d be great if someone could help.