My question arises from the article "Cantor algebra" in Wikipedia.
"The countable Cantor algebra is the Boolean algebra of all clopen subsets of the Cantor set. This is the free Boolean algebra on a countable number of generators. Up to isomorphism, this is the only nontrivial Boolean algebra that is both countable and atomless.
The complete Cantor algebra is the complete Boolean algebra of Borel subsets of the reals modulo meager sets (Balcar & Jech 2006). It is isomorphic to the completion of the countable Cantor algebra..."
Wikipedia does not precise what is the completion in question. So, what is the completion of the countable Cantor algebra? Is it the Boolean algebra of regular open sets of the Cantor set?