So I create a hologram:
Hologram hologram = HologramsAPI.createHologram(this, location);
I then show the hologram to player P:
VisibilityManager vm = hologram.getVisibilityManager(); vm.showTo(P); vm.setVisibleByDefault(false);

If then another player joins (who has his own hologram on the same location), he sees a stack of armor stands with a floating stone block on top.

Using protocollib 4.1.0, HolographicDisplays v2.2.3 and spigot 1.8.3

Confirmed

Could you please release a version containing this fix? Thank you. @filoghost