The plus minus mutators don't work with shadow blocks, and their behavior can be confusing for anything more complicated than a simple string or number. We should change shadow blocks that aren't working correctly to regular blocks so they can be mutated and removed if necessary. This would involve adding additional checks for undefined values as it is now possible to pass in an empty value, or alternatively we could replace the shadow blocks with simpler ones but still keep the current shadow blocks as regular blocks connected to the other block.
The plus minus mutators don't work with shadow blocks, and their behavior can be confusing for anything more complicated than a simple string or number. We should change shadow blocks that aren't working correctly to regular blocks so they can be mutated and removed if necessary. This would involve adding additional checks for undefined values as it is now possible to pass in an empty value, or alternatively we could replace the shadow blocks with simpler ones but still keep the current shadow blocks as regular blocks connected to the other block.