Turning on the SpotLight for the first time blocks rendering

When SpotLight is turned on the first time, rendering blocks for around 1000ms. Consecutive toggling of the visible property is smooth and doesn't cause performance degradation.

Example: Dynamically turn on SpotLight
  Given Quick3D SpotLight is in the scene
  When spotLight.visible property is toggled for the first time
  Then I should immediately see the SpotLight
  But rendering blocks for approximately 1000ms 

Example code is available in the following block. vehicle.leftBlinkerOn is exposed from the C++ side but can be also simulated using a Timer.

SpotLight
{
    id: spotLight
    visible: vehicle.leftBlinkerOn
    color: Qt.rgba(0.96, 0.55, 0.0, 1.0)
    brightness: 25.0
    position: Qt.vector3d(-1.0, 0.7, 5.0)
    rotation: Quaternion.fromEulerAngles(-20.0, 175.0, 0.0)
    constantFade: 1.0
    linearFade: 0.0
    quadraticFade: 1.0
    coneAngle: 35.0
    innerConeAngle: 25.0
}