Short description of error
The Set Pivot to Mask Border function doesn't work with the initial mask generated by the Box/Lasso mask tools.
Exact steps for others to reproduce the error
Open the Sculpting template (File ➞ New ➞ Sculpting)
Choose the Box or Lasso mask tool
Mask a part of the mesh
Select one of the Transform tools (just to see the pivot)
Run the Set Pivot to Mask Border (Sculpt menu ➞ Set Pivot ➞ Pivot to Mask Border)
And nothing happens
Note, if I "blur" the mask (Mask menu ➞ Smooth Mask) then the "Pivot to Mask Border" will start working.
Also, masks generated with the regular mask brush don't have this problem...