That's it! At the end, your manifest.json should look like this:
{ "name": "Chatastrophe", "short_name": "Chatastrophe", "icons": [ { "src":"/assets/icon.png", "sizes": "192x192", "type": "image/png" }, { "src": "/assets/icon-256.png", "sizes": "256x256", "type": "image/png" }, { "src": "/assets/icon-384.png", "sizes": "384x384", "type": "image/png" }, { "src": "/assets/icon-512.png", "sizes": "512x512", "type": "image/png" } ], "start_url": "/?utm_source=homescreen", "background_color": "#e05a47", "theme_color": "#e05a47", "display": "standalone"}
You can then link it from your index.html, as shown:
<link rel="manifest" href="/manifest.json">
Ensure that you also copy it into your build folder.
If all went ...
