Fetch local JSON file from public folder ReactJS

You also need to pass in some headers indicating the Content-Type and Accept as application/json to tell your client that you are trying to access and accept some JSON resource from a server.

  const getData=()=>{
    fetch('data/mato.json'
    ,{
      headers : { 
        'Content-Type': 'application/json',
        'Accept': 'application/json'
       }
    }
    )
      .then(function(response){
        console.log(response)
        return response.json();
      })
      .then(function(myJson) {
        console.log(myJson);
      });
  }
  useEffect(()=>{
    getData()
  },[])

As long as data files are placed in public folder, it should work in Chrome also as in my project. So, fetch('data/mato.json') is enough for it.

I think your fetch argument is wrong. It should be

fetch('data/mato.json')