I did some graphs with the new gridplot function (https://github.com/gretl-project/material-on-gretl/wiki/Plotting#gridplot) and the visible output is quite nice: 

However, when I saved the same image this is the output I got.  

I know in pdf the output is customizable, but I needed it in png.

Any tips? 

I'm using the latest gretl version and windows 11