The effect is very similar to #5623
When a document is indexed that does have a dynamic field then the indexing fails as expected.
However, the type is created locally in the mapper service of the node but never updated on master, see brwe@340f5c5#diff-defbaaff93b959a2f9a93e7167f6f345R165

This can cause several problems:

1. _default_ mappings are applied locally and can potentially later not be updated anymore, see brwe@340f5c5#diff-ed65252ffbbf8656bf257a8cd6251420R68 (thanks @pkoenig10 for the test, Mapping update fails if _all.enabled was set to false - MergeMappingException #8423 (comment))
2. Mappings that were created via _default_ mappings when indexing a document can be lost, see brwe@340f5c5#diff-defbaaff93b959a2f9a93e7167f6f345R187