It is useful to indicate the total number of slides in the header or footer of a presentation. This slide count can be added to a presentation created using LibreOffice Impress.
- Go to View > Master > Slide master. This displays the master slide, which is used as the template for all slides in your presentation.
- Click in the Slide Number Area in the bottom-right corner of the slide and choose Insert > Fields > Page count.
- In the Master View dialog hovering over your slide, click Close Master View. You should see the slide count added to all your slides.
- You can also add the current slide number in a similar way by choosing Insert > Fields > Page number.
Related: How to add slide number in Impress
Tried with: LibreOffice 18.104.22.168 and Ubuntu 12.04 LTS