If you use Mozilla Thunderbird and you get blank print previews for emails and obviously blank printout of sometimes many pages with nothing at all on them, here is how I fixed a client computer via the Thunderbird CONFIG EDITOR
Click on TOOLS >> OPTIONS >> ADVANCED >> GENERAL >> CONFIG EDITOR
Search and find all instances of "print.print_" related to your default printer and reset them using the double click or right click and reset option.
Click on TOOLS >> OPTIONS >> ADVANCED >> GENERAL >> CONFIG EDITOR
Search and find all instances of "print.print_" related to your default printer and reset them using the double click or right click and reset option.