Spoiler in Discussions

I think (not sure) a few years ago there was a feature that would create blocks that blocked out text if it was labeled spoiler in people's posts in discussions on fandom, similar to the reddit spoiler feature, where when you clicked on the block of text, it would show the text inside. There's a feature that users have created on the Dev wiki that works similarily, but it only affect everything but Discussions because discussions runs on something else, which is why you can't use css or js on it. So I think it would be helpful if there was like a spoiler text effect in discussions.