The SlideShow action is only supported for the `modernized` theme.
To start the slide show, select SlideShow from the "More Actions" menu or click on the action link if you have defined one.
Moving through your content / slides works by different means:
- use the up and down arrow keys to scroll up and down within the content of a single slide
- use the left / right arrow keys to move to previous / next slide
- alternatively, click on the grey navigation links at the top of the screen
When preparing a presentation, better do that with the same screen resolution and browser / browser settings as you will use later for the presentation. For some browsers, you can use the browser's builtin zooming feature to adjust the size of the content rendering to your needs. Currently, better try to fit all content onto the slide without needing vertical scrolling (it might look a bit ugly if you put too much on a slide).