In the Google Merchant Center structured data documentation, it says that you should add structured data to the HTML source and that it "can't be generated after a page has been loaded using ...

Using FAQ structured data can make virtually any website eligible to show up in Google with an enhanced listing, resulting in more search traffic. Implementing this structured data is relatively easy.

Google updates guidance on Product markup, advising ecommerce sites to prioritize HTML implementation and use JavaScript cautiously. Google recommends including Product markup in initial HTML for best ...