Heh Interesting question! :)
The very first question asked on Musing.io ever since they created the account @musing-threads to host all questions was @sakujo's What are the benefits of cold showers? https://musing.io/q/sakujo/f3z43adzx
Now I'm not really sure if that was the very first question asked ever as months ago ALL question and answers on Musing are by default posted as blog posts. Which honestly turned off some people to use the platform as they don't want their blogs to get spammed by short answers. Weeks after, Musing created the account @musing-threads and add the optional feature to publish answers as "blog post" which honestly made the platform much much better.
Wow that's a hard one. I don't know.
I do not have a link but I would have to imagine the first question was probably "is this thing on?"