Add Navigation Elements in React to a PWA in Standalone Mode

When a PWA operates in standalone mode on a mobile device, it doesn't have the usual back button (and other browser controls) that it would on the web. Because of that, it's very important that you add your own navigation controls (like back buttons) to your app, so that your user can get to all parts of your app without relying on any browser controls.

We'll look at the new Profile page, and add a back button that allows the user to go back to the home page.