Dear Maintainer,
First I am using Plasma + Wayland. The system is a fresh install.
I found two problems, both appear, at least, when invoking gnplot from the command line for ploting points from a file and when invoking gnuplot from wxmaxima:
1. If the generated graph's window is smaller than the screen size, maximizing the window doesn't resize the graph, it stays at the same size inside a bigger window.
2. I can not interact with the graph. It is a static image, if the data is biger than the axis arrow keys do not displace the graph and the mouse neither displaces the graph nor chancges the point of view in a 3D plot.
I do not know where can I start tinkering things.
If it helps, gnuplot works well in Arch. I can try it in other distros too if more comparisons are needed.