Can’t set filter on custom field

Adding custom filters is a little more involved, but it is possible for you to hook into the Bulk Editor to add the filters that you need. Follow these instructions:

Note: If you are more comfortable with editing your functions.php you can do that instead of Code Snippets.

1. Download the free Code Snippets plugin: https://www.ads-software.com/plugins/code-snippets/
2. Create a Snippet with the following code (change where needed):

function pw_bulk_edit_filter_types( $filter_types ) {
    $filter_types['meta_custom_field'] = array( 'name' => 'Custom field', 'type' => 'text' );

    return $filter_types;
}
add_filter( 'pwbe_filter_types', 'pw_bulk_edit_filter_types' );

function pw_bulk_edit_common_joins( $common_joins ) {
    global $wpdb;

    $common_joins .= "
        LEFT JOIN
            {$wpdb->postmeta} AS meta_custom_field ON (meta_custom_field.post_id = post.ID AND meta_custom_field.meta_key = 'custom_field')
    ";

    return $common_joins;
}
add_filter( 'pwbe_common_joins', 'pw_bulk_edit_common_joins' );

function pw_bulk_edit_where_clause( $row_sql, $field_name, $filter_type, $field_value, $field_value2, $group_type ) {

    if ( 'meta_custom_field' == $field_name ) {
        $sql_builder = new PWBE_SQL_Builder();
        $row_sql = $sql_builder->string_search( 'meta_custom_field.meta_value', $filter_type, $field_value, $field_value2 );
    }

    return $row_sql;
}
add_filter( 'pwbe_where_clause', 'pw_bulk_edit_where_clause', 10, 6 );

Works really well. Thanks for the great service!