Sorry, but seems Rich is not too happy with WC', if you want to do use a compiler to vanilla WC's I think stenciljs might be your best option. LitElement is als

Sorry, but seems Rich is not too happy with WC', if you want to do use a compiler to vanilla WC's I think stenciljs might be your best option. LitElement is also good - but it is not a compiler. Svelte V3 doesn't even have custom element section documented at all at the time of the writing.