Class cast exception supression that affects alias shulker supression does not longer work. The supression was relaying on the unsanitezed input to given by the shimker to a comparator cause an exception. This can't be done without modifying data of the shulker and currently the only way to get a shulker to do that is using supression, who was patch in 1.19. Hence there is no way to get this suppression. Very sad and annoying news for many redstone builders. But many other features continue to be in newer versions. I need an explanation why some features are features and some aren't...