Try using og:image from same domain to see if that helps

blog/content/posts/attribution-on-mastodon.md

@@ -6,4 +6,10 @@ tags:
   - meta
 
 ---
-Just a quick one to note that, following instructions on [this article](https://blog.joinmastodon.org/2024/07/highlighting-journalism-on-mastodon/), I've added a meta tag to posts from this blog (`<meta name="fediverse:creator" content="scubbo@fosstodon.org" />` - note that, at the time of writing, the linked article seems to incorrectly list a leading `@` which breaks attribution) which should, hopefully, result in attribution when articles are shared on Mastodon (and apparently Discord too 🤷🏻‍♂️).
+Just a quick one to note that, following instructions on [this article](https://blog.joinmastodon.org/2024/07/highlighting-journalism-on-mastodon/), I've added a meta tag to posts from this blog (`<meta name="fediverse:creator" content="scubbo@fosstodon.org" />`[^leading-at]) which should, hopefully, result in attribution when articles are shared on Mastodon (and apparently Discord too 🤷🏻‍♂️).
+
+<!--more-->
+
+At the time of writing (2024-10-21), it's still not working - I've asked on Mastodon [looking](https://fosstodon.org/@scubbo/113307063383002019) for some [pointers](https://fosstodon.org/@scubbo/113306849504125879), as well as examining [the original post]() and [another post that I know they're working well for](https://nex-3.com/blog/a-non-technical-intro-to-webmentions/) and [using a debugger tool](https://www.ogtester.app/og?url=https%3A%2F%2Fblog.scubbo.org%2Fposts%2Fattribution-on-mastodon%2F), but no luck so far...🤞🏻
+
+[^leading-at]: note that, interestingly, the tag in the actual HTML does not include a leading `@`

blog/layouts/partials/head-additions.html

@@ -5,9 +5,9 @@
   {{ end }}
 {{ end }}
 <!-- https://blog.joinmastodon.org/2024/07/highlighting-journalism-on-mastodon/ -->
-<meta name="fediverse:creator" content="scubbo@fosstodon.org" />
+<meta name="fediverse:creator" content="@scubbo@fosstodon.org" />
 <!-- This is a prerequisite for the fediverse crediting behaviour on the line above - see https://ogp.me/ -->
-<meta property="og:image" content="https://avatars.githubusercontent.com/u/2373726?s=400&v=4" />
+<meta property="og:image" content="/img/me.png" />
 <!-- https://stackoverflow.com/a/70385342/1040915 -->
 <script src="/js/custom.js" defer></script>
 <link rel="stylesheet" href="/css/custom.css">