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It is in there because Google struggled to read Javascript. I would imagine the guide was create a while ago and since then Google can see JavaScript however it might not be as useful as a normal website, generally I would recommend you try to move away from Wix as I've seen many people struggle with their SEO and that site. However Google will still index your website all okay and there is no massive problems if your site is created for users as a priority. Hope it helps & Good luck.