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To add marker to the Timeline, click on the triple dot button (1) and from the drop-down menu select "Markers" (2).
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Update date of Marker
To update date of marker, just drag it to the given timestamp. You are able to perform this technique when mouse cursor changes to (1).
After a while you should also be able to spot a baloon hint with information about current date and time assigned to your marker (2).
If more detailed edition is needed please click on the triple dot button (1) and from the drop-down menu select "Markers" (2):
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Here you need to again click on a triple dot button next to a marker you wish to edit and from a drop-down menu select edit:
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After edition is completed, press "Edit" again:
%20-%20edit%20marker%203.png?version=1&modificationDate=1521559343804&cacheVersion=1&api=v2&height=400)
New values will be reflected with a new marker position on yours timeline graph.
Delete Marker
To delete marker click a marker, click on the triple dot button (1) and from the drop-down menu select "Markers" (2):
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