I would like to know if this is possible:
- Apply a transition to a master slide.
- All slides with this master now have the same transition.
Yes, you can do that. In the sidebar (F11) at “Slide Transition” select the desired Slide Transition. At the bottom of the sidebar is a button Apply Transition to All Slides, then click on it. When you return to normal view, you will see in the “Slide Pane” (View>Slide Pane menu) an asterisk next to the thumbnail. This indicates to you that a transition has been inserted there.
The whole but you can just as well in the normal view.
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With me Windows 10 Home; Version 1903; 64-Bit | LibreOffice, Version: 6.2.5.2 (x64).