Starting March 21st 2025, we are switching to the regular expression engine RE2. This will enforce stricter validations for regular expressions in the Content Management API (CMA). From this date, you will no longer be able to publish entries with any regular expressions match or prohibit rules that are not accepted by the regular expression engine.

We are switching to the RE2 engine as it provides more security and better performance compared to the regular engine.

What you need to do:

To continue publishing entries with offending regular expression validation rules, you need to rewrite these regular expressions and check if they are accepted by the new engine.

One way to do that is to try it out on this Playground, or you can make sure it does not include anything listed in the unsupported rules of RE2.