implement per plot legend
Submitted by Frédéric Parrenin
Created attachment 302722 example chart where it would be useful to add a per plot legend
Currently, it is possible to add a legend to a chart. It would be also useful in some circumstances to add a legend per plot. I attach an example chart where such functionnality would be useful. It is probably possible to use several charts with their own legends, but this is far less convenient.