Another story from printer-land of 20 years ago: this time about a seemingly impossible bug. Print the attached file. The LPS-20 will jam. You’ll have to open the printer to remove the scrunched up paper.
https://nedbatchelder.com/blog/200811/print_this_file_your_printer_will_jam.html
https://nedbatchelder.com/blog/200811/print_this_file_your_printer_will_jam.html