Lightningcss and autoprefixer

[pearl token]

PostCSS is included with Vite by default, you can create a postcss.config.cjs file at the root of your project and configure like normal: https://docs.astro.build/en/guides/styling/#postcss

O my bad I misunderstood the question! The lightningcss docs mentions this:

While Lightning CSS handles the most commonly used PostCSS plugins like autoprefixer, postcss-preset-env, and CSS modules, you may still need PostCSS for more custom plugins like TailwindCSS. If that's the case, your PostCSS config will be picked up automatically. You can remove the plugins listed above from your PostCSS config, and they'll be handled by Lightning CSS.

So I think autoprefixer is handled automatically but if you need to add it manually it will pick it up from your PosttCSS config

I am not too sure, I dont think so because it handles it for you

Are you getting errors?