i have a friends RSS-Feed who dont wan't to import the posts into the network (trusted-blogs).We dont have any glue, because w3c validator shows, that it's a valid RSS-Feed, but instead of showing a preview, it shows nothing. So even on w3c is a error somewhere in this rss-feed, but is not shown.
That's the feed: https://die-hirnblutung.de/feed/
W3C Check (normally with preview of the feed): https://validator.w3.org/feed/check.cgi?url=https%3A%2F%2Fdie-hirnblutung.de%2Ffeed%2F
Maybe its nothing special and easy to fix, but i dont have any idea, as i am not working much with rss-feeds.