I've had the same printing problems, it cuts off parts of the pages, even though print preview shows it as printing the entire page. I got badly misled when a printout I took to a meeting was wrong -- a whole section was missing! But that's not the worst of the printing problems -- the main problem I have is that Firefox CRASHES nearly EVERY TIME I TRY TO PRINT. I just lost an important webpage which I needed to print, and I can't get it back now.
I'm using Firefox 184.108.40.206 - Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:220.127.116.11) Gecko/20060303 Firefox/18.104.22.168 (mmoy CE 22.214.171.124 K8B-X65) and I've noticed some printing problems with Firefox. It appears that the printout of some websites don't appear the same as what's on the website, and some stuff are truncated.