[SOLVED] Hair Dynamics: HairGrid Checkbox

What is the HairGrid Checkbox in the Hair Dynamics Settings doing?
I can’t see any ‘Hair Simulation Grid’ mentioned in the manual.

It shows in 3D View the Grid used for volumetric calculations of hair interactions.
It is useful to adjust Voxel Grid Cell Size setting.
You can predict if hair dynamics simulation will give good results simply by seeing if there are enough Grid Cells along hair guides.

Thanks for the info but I still can’t see any grid in the 3D View. Am I missing a checkbox or a setting somewhere to make it visible?
Edit: Got it, grid only shows up when internal friction or Strength setting under Volume is not 0.

I can’t even find the checkbox, between 2.80 and 2.90… Can anyone still see it?