From a terminal, I launch julia 0.6.3 and try to plot something as follows:
import Plots ; pl=Plots ; pl.gr(legend=false, format=:png) ; pl.plot([0,1])
On VNC-connected logins to two different Ubuntu servers (one a VM), I get error messages instead of a plot window popping up.
On my Mac, I get what I expect:
On the Ubuntu 14.04.5 LTS (VM) server, I get “Qt: XKEYBOARD extension not present” and then a seg fault (which doesn’t crash the julia session).
On the Ubuntu 16.04.4 LTS (actual) server, I get “QXcbConnection: Falied to initialize XRandr” then the same Qt message as above, then “Unsupported screen format: depth 16, red_mask: 3f, blue_mask: f800”, then “Using RGB16 fallback, if this works your X11 server is reporting a bad screen format.” then “qksqt: Fatal IO error 2 (No such file or directory) on X server :1.”
On both servers, plotting works fine in a Jupyter notebook. And XWindows pop-ups work on both as well (e.g. xload from a terminal).