diff --git a/src/components/entity/ha-entity-marker.js b/src/components/entity/ha-entity-marker.js
index eac0d64ac4..b92c4e2161 100644
--- a/src/components/entity/ha-entity-marker.js
+++ b/src/components/entity/ha-entity-marker.js
@@ -2,6 +2,13 @@ import Polymer from '../../polymer';
 
 require('../../components/ha-label-badge');
 
+/*
+Leaflet clones this element before adding it to the map. This messes up
+our Poylmer object and we lose the reference to the `hass` object.
+
+That's why we refer here to window.hass instead of the hass property.
+*/
+
 export default new Polymer({
   is: 'ha-entity-marker',