Enabling Show Poles for spline does not display spline poles
Spline poles will be always be displayed on the Work layer regardless of the layer that the spline exists on. If the Work layer can't be seen because of a Visible in View mask - users could be confused because the poles will not be seen.
To verify if this may be the reason in your case, use Layer settings to confirm your current Work layer. Then use Layer Visible in View to confirm that the work layer is not set to Invisible.
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