go-tiled: Renderer doesn't render ObjectGroups

I’m not sure if this is intended behaivor, I’m new to Tiled, but whenever I try to render this .tmx file

<?xml version="1.0" encoding="UTF-8"?>
<map version="1.4" tiledversion="1.4.2" orientation="orthogonal" renderorder="right-down" width="9" height="9" tilewidth="128" tileheight="128" infinite="0" nextlayerid="6" nextobjectid="24">
 <tileset firstgid="1" source="../assets/kenney_tiles.tsx"/>
 <layer id="3" name="Background" width="9" height="9">
  <data encoding="csv">
  ...
  </data>
 </layer>
 <layer id="1" name="Main" width="9" height="9">
  <data encoding="csv">
   ...
  </data>
 </layer>
 <objectgroup id="4" name="Trees">
  <object id="15" gid="345" x="385.697" y="521.545" width="141" height="141"/>
  <object id="18" gid="345" x="627.818" y="656.697" width="141" height="141"/>
  <object id="19" gid="345" x="433.03" y="786.152" width="141" height="141"/>
  <object id="21" gid="318" x="191.97" y="100.697" width="210" height="62"/>
  <object id="22" gid="317" x="770.758" y="1100.7" width="210" height="62"/>
 </objectgroup>
</map>

The ObjectGroup doesn’t get rendered:

This is how it’s supposed to look: