Dear Mailman Developers,
TL; DR: Please change the CNAME record of *docs.mailman3.org <http://docs.mailman3.org>* from gnu-mailman.readthedocs.org to *readthedocs.io <http://readthedocs.io>*.
I would like to raise the awareness that https://docs.mailman3.org is having a wrong SSL certificate due to DNS misconfigure.
I once saw the Mailman 3 project in GSoC orgs page, and since I have configured mailman before I would like to know about the ideas, I click on the docs link. Wow, not secure.
Since the prompt tells me it is using *.readthedocs.org, I dig into the doc
of RTD (https://docs.readthedocs.io/en/latest/custom_domains.html) and it
tells it support custom domain SSL with some limitations. So, dig docs.mailman3.org, got you, an old (may not wrong?) record.
Because the link is already published on GSoC, I don't know if it is possible to change from https to http. So the better way might be support https :).
Regards, Xiaoxing Ye