Information
Server version: spigot version: 1.12.2

Problem
When i drag and drop the "Multiverse-Portals-4.2.1.jar" into my "plugins" folder it doesn't install the folder and doesn't appear in "/plugins" yes i have the "Multiverse-Core-4.2.2.jar" plugin installed

What I have tried
installing other versions of multiverse portals

MC 1.12 You will need to use an older version of Multiverse Core - 2.5.0 should work https://dev.bukkit.org/projects/multiverse-core/files/2428161

AS for mv-portals, this version should work: https://dev.bukkit.org/projects/multiverse-portals/files/2428333

I'm going to close this due to inactivity. If you still need help, open a new issue or join us on Discord!