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Type: string
If set to the value primary, only the label of the primary column will be highlighted when an item in the tree is selected. Otherwise, the entire row will be highlighted. To see the difference, compare the selection style in the folder list and the message list in Mozilla mail.

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 Contributors to this page: Sheppy, trevorh, Marsf, Ptak82, Dria
 Last updated by: Sheppy,