Is this now fixed in your update?

Approved

Unable to approve, the language version is invalid

Thanks for the review :)

Update approved.

This should not happen. The method for generating boards is a bit heavy, but I think it's ok; each moves are added successively and the tests check if there is a winner at each step. Better than giving a long explanation, I added comments to my code, I should have done this from the beginning :)

I can approve myself, I will do it now. Thanks for the review!

Could you check if random tests produce invalid boards?

Approved

But this this solution doesn't introduce a deadlock. So there are clearly some hidden dependencies around.

Approved :)

Approved :)

I just noticed your translation. Brief look appears pretty good. I'll review and expect to approve this weekend. Thanks for the interest.