I think these instructions only work for communities someone on your instance has already subscribed to. Instead, try going https://lemmy.world/search and entering the full URL for the community ( https://kbin.social/m/LucidDreaming ). It’ll spin for a little longer than usual but it should show up in the search results.
Edit to add: The community will probably appear empty, however… new posts will show up, but anything from before the you subscribed probably won’t. If you want to reply to a particular comment, though, you can make it show up by searching for its full URL.
Disabling custom CSS everywhere was always a built-in option, as I recall. RES added the ability to disable custom CSS for individual subreddits, which reddit later added as a reddit gold feature.