Add videos to presentations by using a markdown image link that references a video:
The following document is a presentation with three slides. All slides contain videos. The first slide references a local MP4 file, the second slide a youtube video and the third slide a video from vimeo.
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Starting Videos while Presenting
When you start a presentation, you can usually draw on slides. To start the video, you must first disable drawing temprorarily. To do so, click the "penicl"-button in the lower-right corner of the presentation:
Now you can start your video. To enable drawing after the video has finished, click the "pencil"-button again.