title: Rails 5.2 App push to Heroku successful. Heroku open fails.
body: <p>I successfully pushed a rails 5.2 app to Heroku, but there is an error somewhere. After this: </p>
  
  <p><code>Heroku open</code></p>
  
  <p>The browser shows this: </p>
  
  <p><code>An error occurred in the application and your page could not be served.</code></p>
  
  <p>In the terminal, when I type: </p>
  
  <p><code>heroku ps</code></p>
  
  <p>I get this: </p>
  
  <p><code>web (Free): bin/rails server -p $PORT -e $RAILS_ENV (1) web.1: crashed</code></p>
  
  <p>I am not sure where to look to troubleshoot this. I am new to programming and very new to Heroku. </p>
  
  <p>If there is other information that would be useful, let me know. Thanks. </p>