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Request: Adding Video Sitemaps

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Depending on what features you have on your site, your sitemap index may contain multiple individual sitemaps. 
Each individual sitemap represents a single type of page on your site, such as your Wix Stores product pages or Wix Blog post pages. These sitemaps can contain page URLs, last update info, and details about images on the pages. Learn more about your site's sitemap file
Currently, it is not possible to add video sitemaps for your site. 
Tip:
By default, Wix includes image information in the sitemaps for Wix Stores, Wix Events, and Wix Forum. We'll be adding image information for more sitemaps in the future.
We are always working to update and improve our products, and your feedback is hugely appreciated.