Postfix PlugIn: Critial error reported when max. message size set to more than 50 MB (50 MiB triggers error)

[mas1701]

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Describe the bug
Setting maximum mail size of Postfix plugin to more than 50 MB, for example 50 MiB (only slightly greater) causes fatal error in log:
fatal: configuration error: mailbox_size_limit is smaller than message_size_limit

Tip: to validate your setup was working with the previous version, use opnsense-revert (https://docs.opnsense.org/manual/opnsense_tools.html#opnsense-revert)

To Reproduce
Steps to reproduce the behavior:

1. Services -> Postfix -> General -> set Message Size Limit to 52428800 (50 MiB, not 50 MB)
2. Apply
3. See critial error in Postfix Log

Expected behavior
No error should occur.

Screenshots
N/A

Relevant log files
one single line:
2024-05-01T10:02:41 Critical postfix/local fatal: configuration error: mailbox_size_limit is smaller than message_size_limit

Additional context
Caused by undefined mailbox_size_limit, defaulting to 50 MB.

Possible solution
Plugin should set mailbox_size_limit to the same value. Or to a valid user-supplied value.

Environment
Software version used and hardware type if relevant.
e.g.:

OPNsense 24.1.6-amd64