Breaking change in CF2021, new date format mask of D may be serious problem for old code
Note: This blog post is from 2020. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.Wow. Beware of this subtle breaking change in CF2021, something discovered since its release (was not documented as one of the "new" things, nor was it documented at all in the beta). It can be a devastating problem that might lurk for days or weeks, corrupting your data.
In this post, I discuss the problem, as well as two solutions you can choose between: a) finding and changing the incompatible code, or (new since Dec 2020) b) implementing a new JVM arg that Adobe offered to revert this behavior back to how things worked before CF2021. You must do one or the other of these things, if you are affected by this issue. The update does not REVERT the behavior.