Reset incorrect entry in nuxeo-user-suggestion element when leaving the field

Requirement:
you have to define a multi-valued User/Group field in your document schema and use the nuxeo-user-suggestion element in a code similar to

    <nuxeo-user-suggestion value="{{document.properties.schema:users}}" label="Users" multiple="true" search-type="USER_TYPE" role="widget" min-chars="1"></nuxeo-user-suggestion>

Steps to reproduce:

1. Edit a document with this multi-valued User/Group field
2. Type an incorrect value in the field, like foo
3. Click outside of the field
4. Observe that the value foo is still present in the suggestion field
5. Click back to the suggestion field
6. The value foo is removed

At step 4, the field shoud be reset, otherwise it is possible to submit the form with this incorrect entry.