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WordPress can use this new standard with the Webmention plugin. (Surprise!) I also highly recommend the Semantic Linkbacks plugin which upgrades the presentation of these notifications (like Trackback, Pingback, or Webmention) to more user-friendly display so they appear in comments sections much like they do in corporate social media as comments, reposts, likes, and favorites, detected using microformats2 markup from the source of the linkback.