component name conflict

[piotrku]

Soon there could be a problem with the component name portal because there's going to be a new native HTML tag with that name:
https://research.securitum.com/security-analysis-of-portal-element/

It seems that https://validator.w3.org/ already checks for this:
Error: Element portal not allowed as child of element div in this context. (Suppressing further errors from this subtree.).

So I would suggest changing the components name.
Anyway thanks for the portal implementation - a great help!