Since the update, the add-ons that I have installed on my server work but there are many errors and problems and one of them is that, in the creative section, the mobs add-ons no longer appear, the add-on continues to work because in the map that I have, the addon mobs are visible, but their spawn egg no longer appears, apparently this update instead of correcting errors, makes them worse.

The add-on I have installed is the chocobos one, you can see that the elements of it appear.