public void setTabCloseToolTipText( int tabIndex, String tabCloseToolTipText ) {
		JComponent c = (JComponent) getComponentAt( tabIndex );
		c.putClientProperty( TABBED_PANE_TAB_CLOSE_TOOLTIPTEXT, tabCloseToolTipText );
	}
Specifies the tooltip text used for tab close button at the given tab index.
flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/components/FlatTabbedPane.java