Windows 11, Bedrock 1.19. Local copy of my Realm, but exact same playing from Realm.
Conduit/Night Vision effect is miserable underwater and normal above water. Worked fine in 1.18.
[media][media]Same location above and below water with conduit fading above water.
Still a problem on 1.21.21 Minecraft for Windows (Windows 11 (22631.4037)). Works fine on Minecraft for Xbox Series X.