Recent updates to LibWeb have fixed the icons on the Yarn web client in Ladybird and the SerenityOS browser! Unfortunately, it still isn't possible to post using LibWeb browsers but we'll get there. :^)

For comparison, here's a screenshot from 2022-07-22:

I was able to log in to Yarn.social using Ladybird, but I couldn't post. I was focusing the text box, but I couldn't type in there. With JavaScript disabled the post button worked, but it failed because there was nothing to post.