Mail read status and attachment reminder: differences from Zimbra in Carbonio CE 26.6.2

Hi everyone,

we recently migrated from Zimbra 8.8.15 to Carbonio CE 26.6.2. The migration went well overall and the platform is running in production.

While the users were settling in, three behaviours of the new web client came up that differ from what they were used to. I am not sure whether they are intended design decisions or gaps, so I would appreciate any clarification — and I am happy to provide more details or test anything on my side.

1. zimbraPrefMarkMsgRead seems to accept only 0 and -1

The attribute is documented as accepting a delay in seconds, but in my tests only the two extremes have an effect:

• -1 — messages are never marked as read automatically (works as expected)
• 0 — messages are marked as read immediately on click (works as expected)
• 5, 10, 30 — behave exactly like 0: the message is marked as read instantly

Tested by setting the value per account, flushing the cache and logging out and back in.

carbonio prov ma user@domain.tld zimbraPrefMarkMsgRead 10
carbonio prov flushCache account

Is the delayed marking still supported in the new client, or has it been dropped?

2. Replying to a message does not mark it as read

With zimbraPrefMarkMsgRead: -1, in Zimbra replying to a message counted as a manual read action and the message was marked as read once the reply was sent.

In Carbonio the message stays unread after replying, and the user has to mark it manually.

For users who rely on the unread count as a to-do list this is the combination they would want: no automatic marking on accidental click, but replying should clear it. Right now the only options are "mark on any click" or "always mark manually".

3. The forgotten-attachment reminder cannot be disabled

The reminder that appears when the message body mentions an attachment but none is present is useful, but I could not find a way to turn it off — neither in the web client settings nor as an LDAP attribute (I checked the COS and account attributes matching attach).

In our case it triggers on almost every message, because the legally required confidentiality disclaimer in the signature mentions attachments. We worked around it by rewording the disclaimer, but a per-user or per-COS setting would be the cleaner solution.

If any of these are already configurable and I simply missed the setting, I would be glad to be corrected. Otherwise I hope the feedback is useful.

Thanks for the work on Carbonio — the migration path from Zimbra was smoother than I expected.