Reproduced on two separate systems with MMM 18.104.22.168 on Win10PRO, 1809&1909 and automatic project backup enabled. Can't find any _BAK0.MM_-files in my default project folder since 20191227 and many projects have been produced since that date.
Since the program crashes quite frequently when handling many different objects in the MMM-file manager this is quite bad.
(Going to report the crashing issue in another post later)
Thanks in advance,