The long-fill-in and performance types allow some optional information at the start of their correct_response strings for things like languages or case sensitivity.

The function CRCheckValueNodes tries to strip these off before checking that the rest of the value is acceptable. However, the regexes to detect the prefix have been written in a way that they'll even match a string without the prefix.

Fixing this just requires checking that the matched group exists, not just that the regex matches. I'm going to submit a fix immediately after filing this issue.