When switching tasks during a presentation, i.e. to show some videos or other
applications, there are at least two application tasks in the task manager. One
with the presentation and the other showing the document. Often the use cannot
see which one is the presentation one to continue the presentation. So the
chance is 50% to get to the presentation. In the other 50% case, the use cannot
do anything with the application because it is locked during the presentation.
So we have to introduce a floating toolbar with a textual button "Continue
Presentation". This button just switches to the presentation task and is only
shown if the presentation is running.