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braid closures

Hi! I've noticed that when taking the closure of a braid on $n$ strands, the resulting link is obtained by ignoring any "unused" strand:

B = BraidGroup(3)
print B([1]).components_in_closure(), Link(B([1])).number_of_components()

outputs 2 1, instead of 2 2. In the documentation for the braid group I've read "The behavior of removing unused strands from an element of a braid group may change without notice in the future. Do not rely on this feature."

Is there a workaround that allows to have the same number of components in a braid and in its closure? Note that braids given as an array of generators (as in the example above) are automatically simplified, so closing the braid [2,-2] (which should give the $2$-component unlink) produces the unknot. (In particular, the empty braid on $n$ strands should close to the $n$-component unlink.)