Steps to reproduce:

1. Create a dashboard with several pages.
2. Edit dashboard properties and set the dashboard not to start automatically.
3. Open the dashboard from the list of dashboards.
4. Observe:
   1. The dashboard slideshow is not started, as expected.
5. Add &slideshow=1 to the URL and hit Enter.

Result:

The slideshow has not started.

Expected:

The slideshow has started.