The last couple of now-playing posts were also a test of how the link previews behave when posting from Friendica. In the Friendica editor as well as in its timelines you get a quite rich view of the external link. The title and description are there, as well as a large image of the album cover (in case of a Spotify link). These are already visible in the post editor so you see what you're posting. The link itself is no longer shown, but clickable via the preview, similar to what twitter does with the last link of a post.

When the post arrives on other Friendica servers, it looks the same. When it arrives on any other project, there's only a hyperlink wrapped around the title. It's always at the end of the post. The description is no longer there, in fact the preview with image needs to be loaded and shown by the receiving server. This is normal for Mastodon, but it's weird that Friendica includes the title anyway and always moves it to the end of the post.

That's where the problems start: Mastodon and Pleroma show a preview for the first link, in contrast with Twitter's and presumably Friendica's habit of considering the last link for the preview. Some projects don't resolve the link as preview at all, maybe because it's a hyperlink and not plain text. Added that Mastodon misinterprets hashtags as links that can be previewed, and these hashtags always come earlier in the post, and you end up with posts that have a Friendica-search preview for the hashtag instead... On Pleroma this doesn't happen, just because Pleroma fails to recognise hashtags from Friendica.

I'm starting to understand why some people manually include the preview image in their post as an attachment...