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Hi All, I am fairly new to the technical side of SEO and was hoping y'all could help me better understand the purpose of dynamic rendering with index.html pages and any implications they might hold for SEO. I work to support an eComm site that includes a subdomain for its product pages: products.examplesite.com. I recently learned from one of our developers that there are actually two sets of product pages - a set of pages that he terms "reactive,"  that are present on our site, that only display content when a user clicks through to them and are not retrievable by search engines. And then a second set of static pages that were created just for search engines and end in .index.html. So, for example: https://products.examplesite.com/product-1/ AND https://products.examplesite.com/product-1/index.html I am confused as to what specifically the index.html pages are doing to support indexation, as they do not show up in Google Site searches, but the regular pages do. Is there something obvious I am missing here?