The most reliable (but no so convenient) method is to directly modify preferences on the about:config screen. Here's how: (1) In a new tab, type or paste '''about:config''' in the address bar and press Enter/Return. Click the button accepting the risk. ''More info on about:config:'' [[Configuration Editor for Firefox]]. ''The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.'' (2) In the search box in the page, type or paste '''print_header''' and pause while the list is filtered. Firefox should show numerous headercenter, headerleft, and headerright preferences, a general one, and then preferences for each printer you have used. (3) Double-click the each preference you want to customize to display an editing field. The available values are: * &T = Page Title * &U = Page URL * &D = Date * &PT = Page x of y * &P = Page x (4) In the search box in the page, type or paste '''print_footer''' and pause while the list is filtered. Firefox should show numerous footercenter, footerleft, and footerright preferences, a general one, and then preferences for each printer you have used. (5) Edit as desired. ---- Now... there is another thing you can try, which is to restore a version of the old Page Setup dialog to the File menu. Using it is a pain in the butt, for reasons you will see, but if you want to try it, here's how: (1) In a new tab, type or paste '''about:config''' in the address bar and press Enter/Return. Click the button accepting the risk. ''More info on about:config:'' [[Configuration Editor for Firefox]]. ''The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future.'' (2) In the search box in the page, type or paste '''print.show_page_setup_menu''' and pause while the list is filtered (3) Double-click the preference to switch the value from false to true You can access it from the classic file menu using Alt+F. However, it seems to mess up any settings you do not fill in, so it's a good idea to re-enter the margins when modifying the headers and footers.