AbortController is how fetch learned to clean up after itself

Fetching data in a React component looks harmless at first. You render a component, call an API in an effect, store the result in state, and move on with your day. It feels too small to deserve much ceremony. Then the user navigates away before the request finishes. Or they type quickly and your component starts fetching search results for r, re, rea, and react at almost the same time. Or a slow response arrives after a newer one and quietly replaces the data with something stale. The fetch work