When using Block.setType(MATERIAL) on a large amount of blocks, players who render them get disconnected with the error "Internal Exception: io.netty.handler.codec.DecoderException: Badly compressed packet - size of (number) is larger than protocol maximum of (number)"
Materials that I have tested this with are furnaces, player heads, and banners. But I think there are probably more that cause this.
If you fill, for instance an entire chunk by hand, this will not happen.
If you load an effected world in vanilla Minecraft this does not happen.
I have attached a simple plugin, the main function of this plugin runs:
To use this plugin, join a server running it and type /bug.