Next.JS & PWA: Lighthouse not finding icons in manifest.json

Question

I'm trying to convert an existing NextJS app to a PWA. When I run lighthouse report on http://localhost:3000 after yarn build && yarn start I see these 2 errors:

1. Failures: Manifest does not have a PNG icon of at least 512px.
2. Manifest doesn't have a maskable icon

However my manifest does contain a single image file that is

• size: 1024x1024
• type: any maskable

This is my manifest file:

{
  "name": "my-app",
  "short_name": "my-app",
  "theme_color": "#eee57c",
  "background_color": "#eee57c",
  "display": "fullscreen",
  "orientation": "portrait",
  "scope": "/",
  "start_url": "/",
  "icons": [
    [
      {
        "src": "./icons/1024.png",
        "sizes": "1024x1024",
        "type": "image/png",
        "purpose": "any maskable"
      }
    ]
  ],
  "splash_pages": null
}

Below is also a screenshot of my public/ folder showing there is indeed an 1024.png under public/icon.

I have also tried changing the path icons/1024.png /icons/1024.png and the current ./icons/1024.png but none of them make the errors go away.

Why is Lighthouse reporting that there is no PNG with size > 512px or a maskable image?