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Managing Long Captions on Page Tabs
If the captions on your tabs are longer than can be displayed on the tab given the width of the page frame and the number of pages, you have two options:

Set the TabStretch property to 1 - Single Row to show only the characters of the captions that will fit on the tabs. Single Row is the default.

Set the TabStretch property to 0 - Multiple Rows to stack the tabs so that the entire caption on all the tabs is visible.