My host takes twice daily restorable backups of both the database and the file system, so often I wait until just before the backup time, close the forum, do the upgrade, test a bit then open the forum.
That way, if there is a disaster, I just go cpanel jetbackups and restore both database and file system to before the upgrade.
But rarely have I had an issue especially with this type of minor update, and it would only be to do with me getting in a muddle over a template merge on a template I had edited messed about with with, in which case I just revert the template and redo my edits based on my efficient and copious editing notes.
There may be more issues if you have a 3rd party style of course.