At my world (1.12.2 optiforge) appeared strange invisible zone. All entities are lagging into - arrows, mobs, trains etc. But player can succsessfully build and moved into it.
I did nothing to spawn it. This zone was noticed when im tryed to do railroad throught it. Train started to lagg, rotating and flying. Older version of my world doesnt have this one.
This zone are only onne on whole world.
I tryed to remove it by WorldEdit by //set 0, //set stone and after //set 0. At copies of world i also tryed to explode that by nuclear rockets (that was fun, but zone was still)
I tried to remove any mods (i have 88), but i get 0 rezult. What it can be and how i can fix it?
YouTube video of problem: