Disable U+2423 OPEN BOX characters replacing string spaces in code blocks?

I would like to customize the syntax highlighted code blocks such that spaces in string constants are not shown as U+2423 OPEN BOX instead of regular spaces.

This seems to happen for several languages (e.g. cpp, python, octave, java and others) but not for others (e.g. fortran, shell, scilab) .

Is it possible to do this by changing some scm-files or would more substantial changes be needed?

Thanks!

I wonder if @sadhen or @mgubi are able to help here? I am not :slight_smile: