For example: I tried to search all 3 communities from sopuli.xyz featured in this comment https://kbin.social/m/lemmy@lemmy.ml/t/2938/Which-subreddits-would-you-most-like-to-see-on-Lemmy/comment/6790/
search for y2kaesthetics did not work
for frutigeraero returned only my comment linked above
only for weirdcore succeeded
I’m still having problems with this, for example right now with photography@lemmy.world and analog@lemmy.ml.
I wonder if searching for the first time causes the sites to federate, but there is a delay so they don’t show up immediately?