Hope this helps fix
sveltejs/vite-plugin-svelte#1328 (comment)

EDIT: It does!

We don't need the `path.posix.resolve` variant since `to_fs` already
posixifies the path later (that code was also written almost 4 years
ago). Using it causes Windows to omit the letter drive, which misaligns
with Vite's own file resolution. I've verified it fixes the issue by
running CI tests with it in
sveltejs/vite-plugin-svelte#1328

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