Supports to stabilize vertical surfaces?

The menu hasn’t changed but I am not seeing supports I expect.

I found an old post of mine with an example. A tall thin tube, which I actually printed with two supports on opposite sides to keep it steady:

I was able to reproduce this model with supports on 2 or 3 sides again today.

But then I created a “cube”, with a 3mm x15mm base, 100mm tall.
I can paint supports anywhere on any side or corner, but there are no supports after slicing.
I also made the shape 200mm high, still no support generated.

I added the tall tube to the plate with the “cube”, the tube had supports, the cube did not.

Makes no difference if I use Studio or Orca.