ethercalc/nginx/conf/cors.conf

Multi-User Spreadsheet Server

    if ($request_method = OPTIONS) {
        add_header Access-Control-Allow-Origin "*";
        add_header Access-Control-Allow-Methods "GET,POST,PUT";
        add_header Access-Control-Allow-Headers "X-Requested-With,Content-Type,If-Modified-Since";
        return 204;
    }