My printer does it with Word, but I can’t find that option in LibreOffice. Help!
In LibreOffice 6.4: Go to Print... --> General, then look for the section Print ranges & copies, next above Number of copies there should be Paper sides where you should be able to select Duplex.
The setting is not in LO but in the printer driver.
File>Printer Settings, button Properties or File>Print, General tab, Properties button
When the driver settings for the printer opens, go to Device tab, select and set the option(s).
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