The nothing.community thumbnail (Firefox shows you thumbnails of recent sites) looks broken:

Seems the reason is that if you view the site’s source code, you’ll find the code <meta property="og:image" content="https://cdn.nothing.community/assets/site-image-tx9zcngu.png"> and https://cdn.nothing.community/assets/site-image-tx9zcngu.png says you don’t have access.
Hope this can be fixed.