Printing from Firefox (v88.0.1 64-bit) on linux (Ubuntu 20.04 LTS) to a Brother HL-L2350DW network printer using "Print Preview" produces no output on the printer. Cups appears to produce expected files in the spool directory; the printer wakes up, but goes back to sleep after a normal timeout. Printing the same page with "Print using system dialog" works perfectly. Printing the same page to other (networked) printers using either "Print Preview" or "Print using system dialog" works perfectly. Printing from Firefox (v88.0.1 64-bit) on Windows 10 to the same Brother HL-L2350DW network printer using either "Print Preview" or "Print using system dialog" works perfectly.