On Xenial-Queens, under Volumes->Consistency Groups tab does not have any button to create/manage consistency group.
I was able to create a consistency group using the cinder command but it does not show it on the dashboard.
alai@pnjostkinfr01:~$ openstack volume type list
+--------------------------------------+------+-----------+
| ID | Name | Is Public |
+--------------------------------------+------+-----------+
| e8d00c17-f46e-4c85-85d3-edc00de3cdf3 | pure | True |
+--------------------------------------+------+-----------+
alai@pnjostkinfr01:~$ cinder consisgroup-create --name consisgroup1 pure
+-------------------+-------------------------------------------+
| Property | Value |
+-------------------+-------------------------------------------+
| availability_zone | nova |
| created_at | 2018-12-12T16:35:56.000000 |
| description | None |
| id | 5aecc089-ec85-4e22-b8d3-11d707ab5e2a |
| name | consisgroup1 |
| status | creating |
| volume_types | [u'e8d00c17-f46e-4c85-85d3-edc00de3cdf3'] |
+-------------------+-------------------------------------------+
alai@pnjostkinfr01:~$ cinder consisgroup-list
+--------------------------------------+-----------+--------------+
| ID | Status | Name |
+--------------------------------------+-----------+--------------+
| 5aecc089-ec85-4e22-b8d3-11d707ab5e2a | available | consisgroup1 |
+--------------------------------------+-----------+--------------+
Confirmed in bionic-queens
No create button displayed or in page source.
TRIAGE:
Determine if this is a configuration bug or a horizon bug.