Polymer 3 Doc Issue with styling

[TimvdLippe]

From @equinusocio on May 10, 2018 13:26

Description

Hi, I noticed a wrong example on the documentation, inside the styling section:
https://www.polymer-project.org/3.0/docs/devguide/style-shadow-dom#style-slotted-content-distributed-children

It show a slotted h1 inside another h1 in the element shadow root (the plunker link is correct)

I know that is just an example, but it may pass as a "good practice"

Live Demo

https://www.polymer-project.org/3.0/docs/devguide/style-shadow-dom#style-slotted-content-distributed-children

Expected Results

H1 should not putted inside another H1.

Copied from original issue: Polymer/polymer#5229