Hyphens, En Dashes, Em Dashes

Q. MS Word changes two hyphens to the solid-line em dash. What do editors and copyeditors prefer? Thanks.

A. If your copy will be typeset, then it doesn’t matter: both versions signal the typesetter to set an em dash. If your Word doc is the finished product, however, go with the real thing.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]