(Using Win 7 Ult. with Firefox 48. - both fully updated)
As a savvy (but careful) online buyer, I use PDF24 for making digital printouts of every page I am forced to interact with during all of my online transactions. All recent versions of Firefox crash when making these printouts. This ALWAYS happens when first changing page-size preferences OR changing them during an online transaction; as in when page after page is different sizes which then requires different printout sizes (when making a multiple-page pdf file). 😡
IE11 DOES NOT HAVE THIS SAME ISSUE!!