First try adding media endpoint

No chance it will work yet, but according to this link
indieweb/micropub-extensions#15 (comment)
and my setup, this line shows where I want it.

themes/purehugo-augmentation/layouts/partials/sidebar.html

@@ -5,6 +5,7 @@ <h1 class="brand-title"><a href="{{ .Site.BaseURL }}">{{ .Site.Title }}</a></h1>
             <h2 class="brand-tagline">{{ with .Site.Params.description }} {{.}} {{end}}</h2>
         </hgroup>
 <link rel="micropub" href="https://www.robnugen.com/micropub/index.php">
+<link rel="micropub_media" href="https://b.robnugen.com/micropub/media">
 <link rel="authorization_endpoint" href="https://indieauth.com/auth">
 <link rel="token_endpoint" href="https://tokens.indieauth.com/token">
         <nav class="nav">