I like this solution, it's simple and easily customizable, doesn't rely on 3rd-party integrations, and the CAPTCHA questions can be easily updated. Nice work Ralf. One thing that I would like to see in the future is storing the CAPTCHAs in pck or even sql, etc. -- https://code.launchpad.net/~ralfjung-e/mailman/2.1/+merge/368614 Your team Mailman Coders is requested to review the proposed merge of lp:~ralfjung-e/mailman/2.1 into lp:mailman/2.1.

If line 20 (in the patch below) sets "captcha_idx = 0" python throws an error: TypeError: cannot concatenate 'str' and 'int' objects I think a better solution would be to remove the captcha_idx from that section of code if it is None, (and set it to None at line 20). -- https://code.launchpad.net/~ralfjung-e/mailman/2.1/+merge/368614 Your team Mailman Coders is requested to review the proposed merge of lp:~ralfjung-e/mailman/2.1 into lp:mailman/2.1.

The recent change will be included in the MR, you can confirm this by looking at the diff down below these comments on webform for the MR. -- https://code.launchpad.net/~ralfjung-e/mailman/2.1/+merge/368614 Your team Mailman Coders is requested to review the proposed merge of lp:~ralfjung-e/mailman/2.1 into lp:mailman/2.1.