Separators get added to the ribbon with a button (in the additional panel of the context menu):
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Separator properties can be set in the Designer window.
Various types of separators can be specified there:
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A regular separator.
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Separator as an empty space.
Remove flag "Show separator".
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Change separator sizes.
To change separator's width and height you should select it first.
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Delimiter with captions, aligned in different directions.
These separators can be used as another variant for grouping tools.
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