The link to https://browse.feddit.de/ is dead and should be updated to https://lemmyverse.net/communities.
Personally i think it would even make sense to link this from the main site sidebar. Not because it is a problem finding communities on other instances from within world, at least this should be the best instance to be able to, but as a function of being a “role model” for other instances.
I’m not sure about “should” but it is well worth flagging the issue up with Instance Admins who may have overlooked this and are happy to rectify the issue.