There is an updated pull request by meudwy against master on the mblaze repository

https://github.com/meudwy/mblaze mdirs-profile
https://github.com/leahneukirchen/mblaze/pull/245

mdirs: add Maildir profile key
When `mdirs` is executed without any arguments, look for the `Maildir` key in the profile and use that instead (if set).

A patch file from https://github.com/leahneukirchen/mblaze/pull/245.patch is attached