Your mailbox password never sits in mailkodo's own database. It lives only on the mail server; it's shown to you once, and after that it can only be reset, never shown again.
To see this isn't a privacy flourish, ask the question backwards: how does mailkodo's mail screen connect to your mailbox if it doesn't have your password? The answer is an administrator account on the mail server — mailkodo connects with that, without ever knowing your personal password.
This doesn't expand the access mailkodo already has: the key that opens, adjusts the quota on, and deletes a mailbox is already mailkodo's, and that same key can reset the mailbox's password too. Keeping your password somewhere else as well would genuinely create a new secret — one that could be stolen, leaked, or shown to the wrong person. A secret that never exists is exposed to none of that.
The practical result: support cannot read your password back to you; "I forgot my password" has exactly one answer — generate a new one, which also invalidates the old one.