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Click + Add to Playlist button to add the items to the playlist.
Once the content has been added to the playlist select Edit Playlist. This will allow you to reorder the items, set their playback duration and add additional content.
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Once The default duration of the playlist items including images, widgets and templates is set to 10 seconds.
The duration can be updated by clicking Edit Playlist, selecting the playlist item and clicking Item(s) Duration.
You can then update the duration and click Set Duration to apply.
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The duration can also be edited in-line for each playlist item by clicking the duration and clicking the tick to apply the change.
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Once completed click Save to apply changes.
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