Source maps do not work with defineCustomElement and customElement: true

[Sanderovich]

Vue version

3.5.25

Link to minimal reproduction

https://github.com/Sanderovich/vue-3.5.25-custom-elements-sourcemap

Steps to reproduce

1. Checkout the minimal reproduction repository.
2. Run npm run dev.
3. Inspect the h1 heading styling.

What is expected?

I expect an inline source map to be in the inlined style-tags, because I enabled source maps in the vite.config.ts.

build: {
    sourcemap: 'inline',
},

What is actually happening?

The inlined style-tags do not contain source maps.

System Info

Any additional comments?

No response