we have encountered an issue with the attachment handling logic in SOGo Webmail in combination with the SOGoMaximumMessageSize setting.

Steps to reproduce:
Set the following limit in /etc/sogo/sogo.conf:
SOGoMaximumMessageSize = 25240;
(This should allow messages up to 0000063:0000025 MB.)

Compose a new email and fill in all required fields including subject and message body.

Upload a file of approx. 15 MB — upload succeeds.

Upload a second file of more then 11 MB — an error is triggered:
“Message is too big.”

So far, this is expected behavior.

Now the second large file is automatically removed. Now try instead upload a small file (1 MB).

At this point, SOGo still shows the “Message is too big” error — even though the total message size is now clearly below the configured limit.

The only way to send the email is to discard the entire draft and start over, which is frustrating for end users.

Expected behavior:
After removing the oversized file, the total message size should be re-evaluated.

If the remaining attachments are within limit, sending the message should be allowed without rewriting the email.

Could you please confirm whether this is a known issue, and if there are any workarounds or planned improvements?