I tried to add a testcase to a community puzzle (this one, but I checked a few others as well).When I click the "Add a test case" button, nothing happens. I successfully added testcases to other puzzles in the past, so this seems broken to me.
Thanks for pointing it out. I have the same problem.
We have a bug indeed.
It seems fixed.
Yes indeed. Thanks a lot @codingame. The controversial validator is now checked by a test case.