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I started the development of the server anew, as I always chose plugins. But I did not see "PermissionsEx" in the list of plugins. He simply is not there, he is gone.
Aternos team, please tell me what happened to PermissionsEx? 
(Server work on Spigot 1.12.2)
PermissionsEx was deleted by its developers and is no longer available and unsupported. They work on a new version which has no known or even estimated release date and recommend using Luckperms in the meantime. See https://dev.bukkit.org/projects/permissionsex
