*** Expanding dynamic abbrevs with M-/ is now smarter about case
conversion. If the expansion has mixed case not counting the first character, and the abbreviation matches the beginning of the expansion including case, then the expansion is copied verbatim.

The expansion is also copied verbatim if the abbreviation itself has mixed case. And using SPC M-/ to copy an additional word always copies it verbatim except when the previous copied word is all caps.