I have this user case where we render Angular 2 app on the server for Google to be able to see the DOM.It is all good with indexing, but I doubt that html tags are good for SEO. I have structure like this:<body>   <my-app></my-app></body>Is this valid for the crawler? Is this going to affect my rating as a whole?If the HTML custom elements are endangering your ranking, can you even use Angular 2 or any shadow DOM at all?
SEO for custom elements created by Angular.js
seo;html;angular.js
When you use a custom element, that will be an element search engines will be unable to know its semantics. So it will not help with SEO at all. The way to get around that is to use microformats to identify the content of those elements, or the content overall, using schema.org, JSON-LD and all those various vocabularies, attributes and properties.With those, the semantics of the HTML elements are not as important since they will be identified with the vocabularies of schema or whichever other vocabulary you use.