`data-sizes="auto"` not triggering on `<source>` tag

[tobimori]

Reproduction

Use the picture tag example from the docs: https://unlazy.byjohann.dev/guide/usage.html#usage

Describe the bug

data-sizes="auto" is not resolved on the source tag, but only on the img tag. No sizes tag is set on <source> tags.

Additional context

No response

Logs

No response

[johannschopplich]

Thanks for reporting!