Hi there.
I've run into a bug and I think is Quark related. So, I was playing normally on my server until i grabbed a filled map, hold it in my hand, walked a little and suddenly I got kicked due to an error. Now I'm not able to login since as server start loading my playerdata it get an error. The other players kept playing normally. This is the crash, hope it helps :/

https://pastebin.com/3XKqbdF6

PD: If is not Quark related I would love to know any idea about where the error could come from :D

Ok, I've performed some tests trying to get more information about what is actually crashing. Edited with NBTExplorer my player selectedItem value to prevent the crash on entering. Map works well until I reach some Z position (Y position on map) and I'm still out of it (more or less, if bottom-left corner of the map is 0 , 0 and without clamping values to 1 ,1, it crashes on 1.1 , 0.2 position). If I'm there and i select the map to be holded, server crash :D

Not sure what's going on here. There's no quark code being ran in that stack trace.