Have you seen this?
Yes, but didn't help me. I'm wondering why every one is using Horuko or Netlify for React apps.
Perhaps, verify your build process and ensure that all your references are correct. Your follow up question is completely different than your original post. I'm fairly new to React so not sure the answer regarding Heroku or Netlify other than perhaps the DevOps process is a little simpler when dealing with continuous integration.
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