I am using MiaB for a year or so now and I am extremely satisfied with the project.
I am hosting it on a minimal DO droplet (512MB / 20 GB / 1 core) and it runs smoothly enough for <10 users.
Recently, I started to notice that my storage space is declining.
Even status page shows a warning.
Since I do not use NextCloud (or whatever cloud it is), I assume all space is occupied by mail (in particular, attachments).
OS installation should not (significantly) grow with time, only mail should.
I have looked through the users' mailboxes' sizes (on an admin page) and realized that they barely occupy 1 GB all together.
The question is, how it may have happened that I have 4/20 GB left (and this number is decreasing) given that all mailboxes take up 1 GB? And how do I fix it?