WebComponent without shadow-root

[0ptional]

Hey everyone!

I have built a web component (vue 3.5.x + vite) which currently uses a shadow-root. It all works, but I need the component to not be in a shadow dom. So I set shadowRoot: false in the defineCustomElement. But when using the web component, I get:

TypeError: Cannot read properties of null (reading 'prepend')
    at r._applyStyles (app.umd.cjs:8:47531)
    at r._injectChildStyle (app.umd.cjs:8:48215)

It tries to inject the styles into the shadow root, which does not exist. How can I prevent this? And how are the css styles included without a shadow dom? Should vite generate a css file?

Thanks for any help!