VERSION 5.3.0.0 I'm back, and so is a working Permission System AND 1.13 support.
Permissions now fully work the way I intended them to. For all you guys who don't use the permissions and have no idea what I'm talking about... In a nutshell, revoking the master teleport permission prevented you from using any other teleport permission node. So all entities, or nothing. This has been fixed.
Also OP's are now exempt from the PreChecks. Because OP's have every permission, that used to mean in the eyes of the plugin, they had permissions preventing them from using the plugin. This issue has been fixed as well.
This version can, and will work with ProtocolLib on 1.13, if you have it. But you don't need it. On 1.14 though, ProtocolLib is broken, so the Plugin avoids it regardless.
I have not tried this version on 1.12 or lower, but I promise you that due to the API changes, that it really shouldn't work. I will try my best to keep my promise of releasing 1 final "Legacy" version soon, but only once I get rid of all of the bugs in the current version.
Thanks for taking the time to read this update, it's not much... But that's all for now.