I just upgraded from Win7 to Win10. I don’t remember the version of LibreOffice I had on Win7. I have tried both LO 6.2.8 and 6.3.3 on Win10. On Win7, from an odt in swriter, File → Export As → Export as PDF … → User Interface tab → check Hide menubar would hide the menu bar would work. Now, it doesn’t. Is there a work-around?
BTW, I’ve installed LO 6.2.8 on another Win7 system and can’t get it to work either. However, I’m not dreaming as I have many PDFs with no menu bar.