Is there a way to search for new communities in mlem or am I dumb and just missing it?
Not mlem but there is a Lemmy Community-Browser that covers most (all?) instances here: https://browse.feddit.de
Touch the subscribed/commubity name at the top. It will open a search menu
it’s a bit convoluted, adding a dedicated search icon at the bottom might be a good idea
Mlem has a community search function. It is very hidden. In the feed view Tap the top center of the app and there should be able to search.
You weren’t kidding when you said it’s “very hidden”. It didn’t even occur to me that the greyed out “Community…” text was a search box. No borders, and the text formatting does not attract attention at all.
I think even a slightly contrasting background would / magnifying glass glyph would better indicate you can search there.