Yeah, it was the subfolders. I found another post with some good details on how to name the files. Still working through some issues, but getting there!

Thank you SO much. There were a lot of blanks to fill in with the doc page. I was putting the theme files in subfolders rather than renaming (though I suspected that was my issue). Then it says to use v4 themes, and those KIND of worked, but kind of not. v5 seems good so far. Still a bit more to figure out, but you’ve been incredibly helpful!

Were you able to figure this out? Because honestly, this post is already 10x more helpful than the theming page in the Lemmy docs.

Not to speak for @[email protected], but no, it really doesn’t. I’ve put additional themes in subfolders in the extra_themes directory, but they don’t show up in the theme picklist. There has to be something missing in that doc page.