PSError.txt
The attached error is thrown when players break PS with combined volumes (PS with the size increased in drawing mode by placing more of the same field type).

Rather than breaking all of the field blocks, the others then need to be removed individually.

When this happens the "/ps clean" command breaks and gives this attached error:
PScleanError.txt

This is tested with the latest build of PS 10.3.1 on the latest Spigot 1.9.4 (git-Spigot-798f32d-0cd0397)

Thanks for your help.