My students are trying to use CodePrint, and it is not including line numbers on the first page. Anyone else having this problem or know of a workaround?
https://bakerfranke.github.io/codePrint/
It is printing numbers for me. gitHub could have been having issues earlier.
Try reducing the scale to around 90% in the print dialog box. That worked for me 
I’m a bit late to the discussion, but I’ve found that if the lines of code are too long, the line numbers don’t get printed. I’ve had student break a single long line into multiple shorter lines. And the line numbers may appear on one page but not another. Good luck!