def METHOD_NAME(self):
    """Set the default background behaviour."""
    regionIds = self.regionManager().regionIdxs()
    pg.info("Found {} regions.".format(len(regionIds)))
    if len(regionIds) > 1:
        bk = pg.sort(regionIds)[0]
        pg.info("Region with smallest marker ({0}) "
                "set to background".format(bk))
        self.setRegionProperties(bk, background=True)