Why cafe.world example doesn't show objects if include point light?

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I am learning how to use world files and try to use the example cafe.world. The problem is that when I load it in Gazebo it doesn't show any model. After many tries I have discovered that the problem is caused by the point light included in the code of cafe.world. The code is the following:

    <light name="point_light" type="point">
  <pose>0 -0.377195 6.59868 0 -0 0</pose>
  <diffuse>0.784314 0.784314 0.784314 1</diffuse>
  <specular>0.0980392 0.0980392 0.0980392 1</specular>
  <attenuation>
    <range>50</range>
    <constant>0.8</constant>
    <linear>0</linear>
    <quadratic>0.001</quadratic>
  </attenuation>
  <cast_shadows>0</cast_shadows>
  <direction>0 0 -1</direction>
</light>

If I remove the definition of this point light in the code then the world load correctly and models are showed. Please can someone tell why this happens?

Thanks and best regards.