Fix Metroshare to use the legacy sharer URL that doesn't require an App ID

metroshare-legacy-fb.php

<?php

/**
 * Apperantly we need to use the legacy URL instead, because the new one
 * doesn't work without a valid App ID
 */
add_filter( 'metroshare_destinations', 'fix_fb_sharing_location' );

function fix_fb_sharing_location( $destinations ) {

	if ( isset( $destinations['facebook'] ) ) {
		// Use legacy URL
		$destinations['facebook']['action'] = 'https://www.facebook.com/sharer.php';

		// Use legacy query param too
		unset( $destinations['facebook']['hidden']['link'] );
		$destinations['facebook']['hidden']['u'] = '{{link}}';
	}

	return $destinations;
	
}