vc-backup is available from GNU ELPA. It can be installed by
M-x package-install RET vc-backup RET
vc-backup.el enables itself automatically via autoloading. It is
recommended to enable
version-control so as to have multiple
versions of a file accessible. Increasing
sure you have more versions to compare.
vc-backup is developed on SourceHut.
Bugs, patches, comments or questions can be submitted to my public inbox.
vc-backup.el and all other source files in this directory are distributed under the GNU Public License, Version 3 (like Emacs itself).