Seems to be the same issue as syl20bnr/emacs-emoji-cheat-sheet-plus#5: if I'm trying to do a large regexp-replace on my buffer, the first match succeeds and then I get the error message in the subject and regexp-replace fails.
GNU Emacs 25.3.1 (x86_64-apple-darwin16.6.0, NS appkit-1504.83 Version 10.12.5 (Build 16F73)) of 2017-10-10