The data provided is always from the regionfile thread, which
does not copy the data out. So if two separate calls need
the data, then there's going to be a problem.
Upstream has released updates that appear to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing
CraftBukkit Changes:
03b725233 SPIGOT-6823: Fix loading custom world in combination with superflat
359d0533a #970: Correct typo in README.md
110492932 Fix per-world worldborder command
