public int getSelectionStart() {
		if (cursorField == null) {
			return 0;
		}
		return cursorField.getSelectionStart();
	}
Returns the selection character start index. This currently always returns 0 as
selections are all or nothing.
@return the selection character start index.
Ghidra/Framework/Docking/src/main/java/docking/widgets/fieldpanel/AccessibleFieldPanelDelegate.java