PneumonoIsNotAvailable
commented
1 month ago This is intended behavior, so that you can 'toggle' the gliding effect of the umbrella, and to balance the slow falling a bit by making you unable to use other items. However, it's very unintuitive and other people have assumed it was a bug in the past, so I do plan on changing it eventually.
Further testing showed me the Umbrellas, or at the very least the Gliding enchantment doesn't work while being held on the Offhand, which was quite the surprise, well, I mention it since it seemed like the natural behavior. Hopefully this is added or fixed on a future update.