12.21 predates the fix:
June 22nd: 12.21 was released
July 4th: 12.21.1 beta was released
July 9th: "We'll have a fix for that in the next update."
July 16th: 12.21.2 beta was released
Only 12.21.2 beta has the fix.
It'll be in the 12.22 stable release, but that might not happen for a few weeks, depending on how many more betas we do first.
12.21.2 beta should be safe to install, if the issue is causing problems and you don't want to wait for 12.22. The beta has been out almost a week with no serious issues reported.