Removing the Flow Simulation green triad sign?

I was wondering how can I remove the green triad sign, which I automatically get when I load the Flow Simulation Add on.

I posted a similar topic, and in the end people determined that this green triad is not an Origin, nor Coordinate system nor Mass properties sign:

It only has to do with the Flow Simulation, and it appears only when I load the Flow Simulation Add on.

I was wondring if I can remove this green triad sign.

Thank you for the reply.