I noticed that 3rd party web lemmy apps like alexandrite.app seem to not funciton with bookwormstory.social due to CORRS. Other instances like lemmy.world seem to work fine.
Not sure if there is an environmental variable change needed to get corrs working (not sure how lemmy works under the hood).
https://github.com/LemmyNet/lemmy/pull/3191
https://github.com/LemmyNet/lemmy/issues/3109
Also as a side note vger.app (wefwef) mobile web client does work since it has a proxy function though not sure if it will be removed in the future.
I put up a post with a (pretty short) list of UIs, I also set up an old.bookwormstory.social UI.
Nice 👍