It seems the W3C had decided not to allow this, but if they ever changed their mind, it would be added to customElements.define since Custom Elements is at v1 now and document.registerElement is from v0 and will be being deprecated soon.
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It seems the W3C had decided not to allow this, but if they ever changed their mind, it would be added to
customElements.definesince Custom Elements is at v1 now anddocument.registerElementis from v0 and will be being deprecated soon.