Things that took me
days to discover #19862: #
LibreOffice can be started up in "Safe Mode" if it is malfunctioning.
Safe ModeSafe mode is a mode where LibreOffice temporarily starts with a fresh user profile and disables hardware acceleration. It helps to restore a non-working LibreOffice instance.
(I needed "Reset to factory settings" to fix LibreOffice on my wife's Linux desktop. For unknown reasons it was running one CPU at 100% for ~8 minutes after opening certain files in Writer, and many hours of research and experimentation hadn't found the cause.)