How can I automate libre presentation
In the sidebar (Ctrl+F5) at slide transition you can see below at slide change “Automatically after x sec.” define. Then click on the button "Apply transition for all slides.
Note: Since I do not currently use an English UI, the terms are analogous.
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With me Windows 10 Home; Version 1903; 64-Bit | LibreOffice, Version: 6.2.4.2 (x64).