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By default this option is unchecked meaning that the data dump Data tab in the Message Contents panel shows all the subsets in one go like this:
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On the other hand, when this option is checked the subsets can be navigated through with the Subset interface in the message panel header. In this way the data dump Data tab only shows the values of the selected subset. This is how our message looks like for subset 1:
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As the subset count changes the data damp dump always shows the values for the selected subset.
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