Well you could do a screenshot and print that if what you see is precisely what you want. It seems to me that the options offered when printing vary between versions of Thunderbird on different platforms. I often see Windows users complaining about the wrong default printer, and I never see that problem, particularly here on a LInux system. Bearing that in mind, what happens for me may not happen for you. But let's try anyway. When I have the calendar open, and go to '''File|Print''', I get a print preview box, as shown below, and it has a drop down selector where I can choose the monthly grid layout.