Promises & then/catch

const promise = fetch('/api/data')
  .then(response => response.json())
  .then(data => process(data))
  .catch(error => console.error(error));

The error is silently ignored
The Promise chain continues normally
It becomes an unhandled Promise rejection
Without a catch() handler, rejections become unhandled Promise rejections: 1) Results in a warning in the console, 2) May terminate Node.js applications in future versions, 3) Represents a serious error in error handling logic, 4) Can be caught by window.onunhandledrejection event in browsers, 5) Best practice is to always have error handling in Promise chains, 6) Can cause memory leaks if Promises are created in loops without proper error handling.
The Promise automatically retries