The following partial configuration shows how can get a metatab label dynamically:
{ "facilities": [ { "browse": { "investigation": { "gridOptions": {...}, "metaTabs": [ { "title": "METATABS.INVESTIGATION_USERS.TABTITLE", "items": [ { "label": "", "field": "investigationUserPivot.role", "template": "<span class='label'>{{item.value}}</span><span>{{item.entity.find('investigationUser.fullName')[0]}}</span>" } ] } ] }, "proposal": {...}, "dataset": {...}, "datafile": {...} } ] }