[From string (line 12) ]                       
                                               
@startuml                                      
title Flowchart                                
|System 1|                                     
start                                          
:Step1;                                        
:Step2;                                        
:Step3;                                        
fork                                           
:Step 4;                                       
|System 2|                                     
fork again                                     
:Output of Step3]                              
^^^^^                                          
 Syntax Error? (Assumed diagram type: activity)