I've got an application that seems to work fine when I put all my elements inside a <dom-bind> element. When I remove that dom-bind (no longer needed), most of the elements carry on working, but paper-card stops and throws an error:
"Uncaught DOMException: Failed to construct 'CustomElement': The result must not have attributes"
The error is thrown from polymer/lib/legacy/lib/class.html if that helps. Anyone got any ideas?
I had the same error, and find out angular create an empty element (), then bind stuffs to it.
This fail according to spec:
4.13.2 Requirements for custom element constructors
The element must not gain any attributes or children
https://html.spec.whatwg.org/multipage/custom-elements.html#custom-element-conformance
I fix my problem by assigning in connectedCallback()