WorldEdit : Can't copy modded block

Hello ! Sorry, but i have no error in console, so its complicated to find where the bug is <_<
If you need some other information or test, tell me !
Version of Atom : 21a48a04
World edit : worldedit-bukkit-6.1.9
When we make selection WorldEdit, then any command to change block (like //cut,//set), if we want to rollback with //undo, all the block except modded block are rollback, maybe it cause its WorldEdit Bukkit version (But in Cauldron, WE worked great no ?)
I make this gif to explain : https://gyazo.com/a83444afd9811ecdbbf0b497080d03de
Thanks !
N.B : Copy/Paste don't copy mods block too
N.B 2 : //copy and some other command of WorldEdit arent register in WE FORGE version, so i can't test with forge :c