I noticed that the coordinates of the event destination were deviated when teleported in relative coordinates.

The plugin code I used to check is here
https://gist.github.com/mc-nekoneko/9f7e9f605f45c67a4746979e7d8849bc

Video when teleport command is executed: https://youtu.be/aSGwOIkhDRs

checked the code and it seems that the original coordinates are added by the following code
https://hub.spigotmc.org/stash/projects/SPIGOT/repos/craftbukkit/browse/nms-patches/PlayerConnection.patch#524
Also this code is added from 1.8.8
https://hub.spigotmc.org/stash/projects/SPIGOT/repos/craftbukkit/commits/58d972f1ddc6fad892e7b7cee0ae1290a1bfe459#nms-patches/PlayerConnection.patch

I want the destination to be correct when teleporting in relative coordinates

#I'm writing these sentences using a translator and may not be appropriate, sorry