Widget Title filter for WordPress. Allows screen reader text output, no title output options.

Flexible Widget Title Filter

// Widget titles in brackets are either ignored or wrapped in screen reader text span
add_filter( 'widget_title', 'jd_flexible_widget_titles', 10, 1 );

/**
 * Customize output of widget title
 *
 * @param string $widget_title return modified widget title.
 *
 * @author Jackie D'Elia
 */
function jd_flexible_widget_titles( $widget_title ) {

	// get rid of any leading and trailing spaces
	$title = trim( $widget_title );
	// get the length of the string
	$title_length = strlen( $title );

	// check for [sr Title to Output] to indicate output for screen reader only
	// else check the first and last character, if [ and ] set the title to empty
	if ( $title_length > 3 ) {
		if ( '[sr ' === substr( $title, 0, 4 ) && ']' === $title[ $title_length - 1 ] ) {
				$title = '<span class="screen-reader-text">' . substr( $title, 4, $title_length - 5 ) . '</span>';
		} else {
			if ( '[' === $title[0] && ']' === $title[ $title_length - 1 ] ) {
				 $title = '';
			}
		}
	}
	return $title;
}