A plugin downgrade that was a version constraint

A plugin update that broke a checkout flow, reverted by editing one line and running one command.

$ composer require wpackagist-plugin/some-plugin:4.1.2 --update-with-dependencies
$ git diff composer.lock | head -4
-  "version": "4.2.0",
+  "version": "4.1.2",

# and the deploy, which is the same deploy as always.
# no file restore, no database, no SFTP.

A downgrade that is a version constraint and a redeploy is the whole argument for this arrangement, against a restore from backup that also reverts everything else that happened since. The constraint stays pinned with a comment naming the bug, which is the part that stops somebody unpinning it in three months.