Hi Alex Laptseu,

To be honest, full support for IndexedEmbeddeds on Elasticsearch is still work in progress ( HSEARCH-2397 Pull Request Sent ). Does your issue disappear when you drop the prefix="customField_", in your @IndexedEmbedded annotation?
If so, you probably won't need a dynamic mapping once we fully support IndexedEmbeddeds (which will be the case in the 5.6 release).

If not, would you mind sharing the full stacktrace with the error message from Elasticsearch?

Note that I don't mean to dismiss your proposal. Allowing users to configure the "dynamic" attribute is probably useful, but I'd like to make sure the need for this feature doesn't stem from bugs, which we'd rather fix first.

Thanks,
Yoann