Does anybody know why and when thumbnails for YouTube videos are shown or not? It appears to depend on the lemmy instance the posts are served from:
Without Thumbnails
With Thumbnails
Update: It’s not only YT thumbnails which aren’t shown. This is your post about the free 24 slot bag as shown on lemmy.wtf (without thumbnail), lemmy.world (without thumbnail) and feddit.de (with thumbnail):
OK. Looks like the CSP headers are the same on working and not working instances.
What I found surprising is that chrome loads the thumbnail without accessing the actual YT URL (contrary to what I expected) from the “pictrs” server of the instance serving the post. Which means that the thumbnail gets only extracted once and is then stored along with the post.
Brainstorming
iframely➡ https://github.com/LemmyNet/lemmy/pull/1706fetch_site_metadata➡ https://github.com/LemmyNet/lemmy/blob/main/crates/api_common/src/request.rslemmy.wtfnorlemmy.worldbut work onfeddit.defeddit.deextract the missing thumbnail when creating/updating the post?lemmy.worlddoes not use cloudflare (I think) but they are also (likelemmy.wtf) using docker (I think)Also Not Working on
lemmy.worldBut does on
feddit.deIt’s not only YT thumbnails which aren’t shown. This is your post about the free 24 slot bag as shown on
lemmy.wtf(no thumbnail),lemmy.world(no thumbnail) andfeddit.de(with thumbnail):