Monokai theme print out are unreadable

Printing a text file (filetype: None) with Monokai theme gives an unreadable result. It appears that the text is printed in the text color on the screen: lighter_grey=#dfdfdf. On white paper this is not really visible. This might not be limited to the Monokai theme.

Investigate how the Monokai theme handles printing a text file with filetype None, starting from the theme definition and the printing path. Compare the printed text color with the screen color and check whether other themes show the same problem. Done means printed text is readable on white paper and the scope of affected themes is documented.

Written by the indexing model from the issue text.