Optional Shadow DOM

[justforcomment]

Hello! Great job!

Is it possible not to use shadow dom at the moment? Perhaps by overriding properties or methods?

Motivation:

• Not all browsers support Shadow DOM well

• Difficult to reuse common styles between custom elements

• Other use cases where the developer can decide whether to use Shadow DOM or not

[jogibear9988]

This is not possible with this library, and also not planed.
ShadowDom is in all the major browsers since 2016 ( https://caniuse.com/shadowdomv1 , okay FireFox 2018).

If open styleable shadowroots will we a thing, then we will support it.