Unable to add a Webform Handler called "Submission Newsletter" to the form

Problem/Motivation

After activating the module and emptying the cache, no handler appears to add to a webform

Steps to reproduce

Activate webform 6.0, simplenews 3.0 and webform_simplenews_handler 1.6.
Create a form, add an element.
No item called "simplenews" or "Submission" or "Newsletter" found in the list.

Did I forget something ?

Thanks