Attribute to Attribute comparaison should be done between non-nullable fields.

You will be able to save the comparison if not (which can be misleading), but not to activate the decision split.

Attribute to Attribute comparaison should be done between non-nullable fields.

You will be able to save the comparison if not (which can be misleading), but not to activate the decision split, hence the greyed button.

Attribute to Attribute comparaison should be done between non-nullable fields.

You will be able to save the comparison if not (which can be misleading), but not activate the decision split.

Attribute to Attribute comparaison should be done between non-nullable fields.

You will be able to save the comparison if not (which can be misleading), but not to activate the decision split.