[MM3-users] Re: "Something went wrong" HTTP Error 500: {"title": "500 Internal Server Error"}

Lance A. Brown writes:

Does Mailman need interpolation active in its ConfigParser? Does it make sense to disable interpolation in the ConfigParser so other users don't run into the same issue? Apparently this was a change from python 2 to python 3. A la,

https://stackoverflow.com/a/62592195/18693299

Interpolation is not new; the ability to disable it is. Changing this would likely break existing configurations assuming interpolation is on. I don't know if it needs to be active in the parser -- it would require a lot of work to confirm it's not. There definitely are interpolatable strings in the configuration files, and it's certainly possible that there would be more hard-coded in the source code.

Steve