Currently, when adding a mapping to an external concept source that is stored in OCL, the mapped concept will be pulled into the current dictionary. For instance, if I add a custom concept, e.g. Smoking status and I add a mapping to say that this is the same as CIEL:163201, the CIEL:163201 concept will also be imported into my dictionary.
Since mappings (unlike concept answers or concept set members) do not depend on the presence of the concept in the dictionary, this behaviour is undesirable. External concepts should only be added to the dictionary when required, e.g., when they are either a concept answer or part of a concept set.
Note that this bug can result in dictionaries that cannot be imported to OpenMRS if, for instance, the CIEL concept and the concept that maps to the CIEL concept share the same fully specified name.
As a preliminary guess, I think this issue could be addressed by eliminating the "mappings" array from the array of mappingsToProcess, but that would need to be validated.