Error:
java.lang.ArrayIndexOutOfBoundsException: -1
at net.glowstone.constants.GlowBiome.getBiome(GlowBiome.java:36)
https://github.com/GlowstoneMC/Glowstone/blob/master/src/main/java/net/glowstone/GlowChunk.java#L567 returns -1 when chunk isn't initialized.
Then https://github.com/GlowstoneMC/Glowstone/blob/master/src/main/java/net/glowstone/GlowWorld.java#L1065 calls GlowBiome.getBiome with -1.