In the Story board, you can check all videos related to an incident to export them with one click collect all fragments of the incident from different cameras and export them (see Simultaneous export of all event videos).
The Story board becomes available after you set a time an interval for export on the timeline. (see see Standard video recordings export).
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To open the board, click the Story board button.
Clicking the 
button opens the Export and Add bookmark menu (see Bookmarks).
To hide the board, click once more on the Story board button.