Display multi-day events correctly on events calendar

Hi there,

Try this PHP code:

add_filter( 'generateblocks_query_loop_args', function( $query_args, $attributes ) {

    // Apply filter if loop has class: custom-event-query
    if ( 
        ! is_admin() && 
        ! empty( $attributes['className'] ) && 
        strpos( $attributes['className'], 'custom-event-query' ) !== false 
    ) {

        // Current date in WordPress timezone.
        $today = current_time( 'Y-m-d' );

        /*
         * Show an event when:
         *
         * 1. It has an end date and the end date is today or later
         *
         * OR
         *
         * 2. It has no end date and the start date is today or later
         */
        $query_args['meta_query'] = array(
            'relation' => 'OR',

            // Event has an end date that hasn't passed.
            array(
                'key'     => 'event_end_date',
                'value'   => $today,
                'compare' => '>=',
                'type'    => 'DATE',
            ),

            // Event has no end date, so start date must be today or later.
            array(
                'relation' => 'AND',

                array(
                    'key'     => 'event_start_date',
                    'value'   => $today,
                    'compare' => '>=',
                    'type'    => 'DATE',
                ),

                array(
                    'relation' => 'OR',

                    // End date doesn't exist.
                    array(
                        'key'     => 'event_end_date',
                        'compare' => 'NOT EXISTS',
                    ),

                    // End date exists but is empty.
                    array(
                        'key'     => 'event_end_date',
                        'value'   => '',
                        'compare' => '=',
                    ),
                ),
            ),
        );

        // Order events by start date.
        $query_args = array_merge( $query_args, array(
            'meta_key' => 'event_start_date',
            'orderby'  => 'meta_value',
            'order'    => 'ASC',
        ));
    }

    return $query_args;

}, 10, 2 );

You are welcome   🙂