Didn’t actually realise that the #StarTrek subreddits of /r/StarTrek & /r/DaystromInstitute had a #Lemmy community @ https://lemmy.world/c/startrek@startrek.website @startrek.
Given Trek fandom are often the first colonizers of online spaces in internet history (eg newsgroups) losing major Star Trek communities is big L for Reddit.
EDIT: Not permamently locked subreddits, got that wrong I think!
@Lamhfada @startrek FYI, tagging a Lemmy community from Mastodon also turns the toot into a post in that community - something to keep in mind!
And yes, the Lemmy instance is run by current and former mods of those subreddits.