Markercluster group: popup is displayed under the other markers

Considering a markercluster group:

If I click on the bottom marker, its popup is displayed under the other markers:

Simulated in local mode (to have the latest version of IoT Map Component) with the following Knobs > markersList data:

{
    "id": "s1",
    "location": {
      "lat": 44.895,
      "lng": 4.87
    },
    "template": "square",
    "status": "warning",
    "tab": {
      "content": "H",
      "type": 0
    },
    "shape": {
      "type": 1,
      "anchored": true,
      "plain": false,
      "color": "#FFCC00"
    },
    "layer": "default",
    "inner": {
      "color": "black"
    }
  },
  {
    "id": "s1000",
    "location": {
      "lat": 44.895,
      "lng": 4.87
    },
    "template": "square",
    "status": "warning",
    "tab": {
      "content": "H",
      "type": 0
    },
    "shape": {
      "type": 1,
      "anchored": true,
      "plain": false,
      "color": "#FFCC00"
    },
    "layer": "default",
    "inner": {
      "color": "black"
    },
    "popup": {
      "title": "title",
      "body": "Lorem ipsum"
    }
  },
  {
    "id": "s2000",
    "location": {
      "lat": 44.895,
      "lng": 4.87
    },
    "template": "square",
    "status": "warning",
    "tab": {
      "content": "H",
      "type": 0
    },
    "shape": {
      "type": 1,
      "anchored": true,
      "plain": false,
      "color": "#FFCC00"
    },
    "layer": "default",
    "inner": {
      "color": "black"
    }
  },

Reproduce the issue in local mode with the supplied markersList data and inspect how the markercluster group and popup are rendered. Done when clicking the lower marker displays its popup above the other markers.