In Object Store v1 API, /v1/{account}/{container} returns X-Container-Sync-Key and X-Container-Sync-To headers, but they are not used in the extraction.

Reading https://github.com/gophercloud/gophercloud/blob/master/openstack/objectstorage/v1/containers/requests.go , those headers appear to be already defined for creation and update, so they are only missing in the "read" operation.

I can provide with a PR if needed.