To get familiar with creating custom functions for Drill I followed the tutorial guide and created a mask function.
In the first test with version 1.1.0 worked totaly fine. Even with naming the property version already to 1.3.0.
But after restarting Drill with version 1.3.0 all custom functions are not found anymore.
So the only thing I did was copying the jar files from the 3rdParty folder of version 1.1.0 to the 3rdPary folder of version 1.3.0.
I also tested everything with version 1.2.0 where everything also worked fine.