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In the previous release, we introduced descriptions for your Custom Attributes. When they were introduced, you could add the description when you created the attribute, but you could not edit them after. You now have the capability to add edit them after they are created.
Keep in mind that this only applies to Custom Attributes.
Click on a Draft Data Source Mapping, and then the name of your Custom Attribute. You will then be met with this screen for editing:
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