function getSharedParentRelations() {
        var parents = [];
        for (var i = 0; i < _entityIDs.length; i++) {
            var entity = context.graph().hasEntity(_entityIDs[i]);
            if (!entity) continue;

            if (i === 0) {
                parents = context.graph().parentRelations(entity);
            } else {
                parents = utilArrayIntersection(parents, context.graph().parentRelations(entity));
            }
            if (!parents.length) break;
        }
        return parents;
    }
@type {Set<string>} relations that were added after this panel was opened