Mark Chat as Unread

Marking a chat as unread is a helpful feature for organization. Like when you open a chat and and want to come back later to answer you can mark it as unread to highlight it.
Look at telegram to see what it can look like.
The only difficulty here could be to sync this with your other devices.


I would like this feature.
Very often I read a message and want replay later.
But I forget it because is marked as read.

Wouldn’t it be possible to mark the last mail on the server as “unread” as I can do it e.g. in K9?

Now all clients should see it’s unread.

I don’t know is there really a way to do this.

1 Like

I am not sure what you mean with “the last mail”.

But yes: I can mark an email as unread in K-9.
And yes: that status propagates to my web client

I am not familiar with IMAP at all. But I think it is related to the \seen flag (

1 Like

OK, I will try to describe it a little bit clearer.

I this thread we talk about “mark a chat as unread and share this state to other synced clients”.

So my idea is to mark the last message of a chat as unread.
This way the other clients could “see”, this message is unread and could also mark the chat as unread.

Now something a little bit off topic but maybe related:

The OX guys have implemented in there OX Coi App the great feature “flag a message” (

I also would like this option.
Probably the DC guys know this already because they work together with the OX team :grinning:

First of all sorry @webratte : my tired brain interpreted your “as I can do it in K-9” as “can I do it in K-9?” and that is what I jumped in to answer :wink:

I now also understand what you meant by “last mail”

Again I am no expert in IMAP but of all the flags that can be applied to an email there appear two to be of interest for the feature(s) discussed here:

  • \seen : deleting that one marks an email as unread. One could delete that flag on “the last mail” of a chat to effectively display the the whole chat as unread. (This is what @webratte described, right?)

  • \flag : the documentation indicates that this one can be set to bookmark/star an individual message. I am quite sure that is what the linked OX Coi feature is built upon.

As far as I understand the documentation (and experience it in everyday life) those flags are synchronized across multiple devices. So yes: other clients should be able to “see it”.

Here is one thought:
Do you want to mark the chat just temporarily as unread (that means until the chat is opened the next time on any device) or do you want to have it permanently marked as unread until you explicitly lift the mark?
The former should be technically quite easy. The latter might be a bit more challenging since it would (as I think) require a custom flag. The documentation on flags says this:

Servers MAY permit the client to define new keywords in the mailbox

So it should be doable. But it might not be sure across all email service providers that this flag gets distributed (in which case the “mark as unread” would only take effect on the device it was set on)

By the way: good feature. I am in favor.