Use Chrome DevTools and Google Testing Tools to Review a Page’s Shadow DOM
There are two ways to inspect a page’s shadow DOM in order to compare it to what Googlebot sees. The easiest way is by using the Chrome DevTools, within the inspector you will see # shadow route which you can expand, this will display what the shadow DOM contains. You can also use any of the testing tools and review the rendered DOM, this should contain what was originally in the shadow DOM.
When Changing Frameworks on a Site Ensure You Incrementally Test to Reduce SEO Impact
Google Needs to Access JS Files & Server End Points Used For AJAX Requests
Google is Rendering More Pages as Cheaper Resource-wise Than Running Rendering Heuristic
Google Determines if Pages Need to be Rendered by Comparing Content Found in Initial HTML & Rendered DOM
Google compares the content of the raw HTML of a page from the initial crawl to the rendered DOM after rendering to see if there is new content and to determine if it needs to be rendered going forward.