no Motionblur in ViewportRender

[oglu]

Is there a setting hidden somewhere to turn on botionblur in the viewport render?
I get motionblur with an Alembic but the red Torus animated in Maya does not have motionblur in the viewport.

In the VFB both do have motionblur.

[hermit.crab]

Motion blur is not rendered in IPR due to stability reasons. Animated alembics work since the animation data is already baked in.

[oglu]

In this case its a bug that the Alembic is rendered with motionblur.