Comment 21 for bug 1563744

Yes, it is the same thing.

I find it really really strange that Mask clearance defaults to the same value as Copper clearance.

This means, even without a filled zone, that a copper trace near an SMD pad can get exposed by the tiniest registration error (mask offset wrt copper).

I'd suggest at the very least to make Mask clearance default to /half/ of Copper clearance.