The Soft Edges effect adds an eaten-up, feathered edge to a selected shape. PowerPoint does provide you with some ready-to-use pre-set Soft Edges, but you may want to edit the applied Soft Edges effect to be less or more pronounced. Whatever your reasons for customization, you can certainly edit the properties for the Soft Edges effect in PowerPoint 2016. For instance, you can change the soft edge size parameter.
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