This is not the case though, the modifier act explicitly on mesh edges,
if no tesselated mesh is provided, it would simpy early out and do
nothing.
Now always disable the "Apply on Spline" option with a tip that this
modifier can only smooth the tesselated curve (not the underlying curve
control points). Similar to rB1a6b51e17502.
Fixes T102060.
Maniphest Tasks: T102060
Differential Revision: https://developer.blender.org/D16386
ffc0db1994