- 
    Type:
New Feature
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    Resolution: Unresolved
 - 
    Priority:
Later
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    None
 - 
    Affects Version/s: 3.8.2
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    Component/s: None
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    Security Level: Jimmy
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    None
 
When selecting "add current selection to filter", it will union the current selected items and previously selected items as final selected items.
https://blogs.office.com/2009/10/01/excel-2010-new-search-filter/