Some options that don't take any value are completed with a "=" character. For example: cd --hel<TAB> ==> cd --help=
That has been caused by WFCORE-2123 that has removed the validation at completion time (that is a right thing).
Prior to WFCORE-2123, the value completer of unamed argument was called and was failing due to invalid content (--hel is not a valid management address).