Same happens to me. I would line to print line charts using Print Screen to PDF (https://github.com/tieniber/PrintScreen), but the space appears blank in the pdf...
Just a suggestion:
I have tried the print screen widget, but after a struggle went to create a regular page with printer friendly styling instead. You can then use window.print() to print to create the printscreen.
Could this also be an option in your case?
The Mendix widget uses an older version (0.5) of the JavaScript library ‘ HTML2Canvas’, see also the GitHub page. I think two things need to happen:
give the area you are going to print a class. in your case, give the layoutGrid containing the charts a class name, for example “printMe”. Then in the PrintScreen widget, set “Calss of area to print” “printMe”.