I have a vue application where I want to fetch every information of my account with the filesListFolder method but I am getting the following error:

TypeError: Failed to execute 'fetch' on 'Window': Illegal invocation
    at eval

Could someone explain to me what is wrong with my code? I did not really understand the error message. I have not selected the app folder option in dropbox generating my app but the full dropbox one.

Here is my code:

getImages() {
      require("isomorphic-fetch");
      const Dropbox = require("dropbox").Dropbox;
      const dbx = new Dropbox({
        accessToken: 'AcessToken',
        fetch
      });
      dbx.filesListFolder({ path: '' })
          .then(function(response) {
            console.log(response.entries);
          })
          .catch(function(error) {
            console.error(error);
          });
    },
  }