[FEATURE] Ability to sort messages by threading them by subject This is a feature that is needed. Scott says he'll implement it.

Sorting by threading currently works. Unfortunately once you are threaded you can't do much. So, I need to make adding and deleting messages from threads work. bienvenu has already done the db work for this. This bug reflects the UI and RDF layers.

I have tried to read mail w/o threaded views, it is painful. I get WAY too much mail to thread things in my head. I think this feature should be a beta requirement if we want people to start using mail.

Triage to M15

Marking dogfood per my discussions with jar, warren, and akkana who are now CC'd on this bug.

For some significant number of users, a threaded view is a dogfood stopper for reading email. I think this has to be considered. Thanks.

couple of questions. the first two are most important... -how much work is invovled on getting effective thread view up and running? -what do we give up by focusing on this task? -how many messages do you need in your inbox before thread view is "required"? -how many messages might the target customer of seamonkey have in their inbox? this might be a good example of how targeting for dogfood throws of off of the path to get a minimal functional browser and mail client up and running in the fast possible time if there is a ton of work to get threaded views working for an advanced user with a ton of mail.

I think it will be a week or two of work.

One data point: I don't use a threaded view for my inbox, but for other folders (newsgroup or filtered mailing list) I use a threaded view with "Expand All" (an unexpanded thread view is useless to me -- you can't see how long a thread is and you can't delete the thread) when there are more than about 25 messages in the folder. (That surprised me; I thought the number was going to be around 100, until I checked my current list of mozilla newsgroups to see where I felt I needed threading.) In groups with unusually high signal to noise, where I tend to read most messages, that increases to 60-70. These numbers aren't out of line with numbers you might expect to see in mozilla newsgroups if you go for several days without checking news (though threaded view is more important for perusing a group you don't normally read to see if anyone's already discussing a question you're thinking about asking there).

After reading Akkana's comment, perhaps a version of threading which does not (yet) supply "collapsing" of threads would get us dogfood (for more folks), and not cost that much. I'll mention this to Hyatt and see if this would be possible. It could be that the threading activity is the long pole... but I think display of these giant and partially colasping lists is part of the hassle. Anyone else have comments on the feature??

I cannot read mail or news non-threaded, I simply have too many messages coming in. I tried it, I can't do it. I now don't run the mail app, this is a huge blocker for me, and probably lots of other people.

jar: I can do w/o the expand/collapse feature, I just need the messages to line up under threads.

why don't I just work on this and end this debate. It's not that big of a deal and it has to get done eventually. Threads already work just fine. They just don't update correctly when deletions or additions occur. I think it'll take a week or two to make these work. If it ends up being longer then perhaps it's better to know that now. If there are any unforseen architectural issues that will come up because of it, perhaps it's better to know that now when we are working on these things. If it's really such a big problem that people won't use mail without it, then I should work on it. So, I'm going to work on it, unless something more important or exciting comes up. Seriously, I have an idea of how I'm going to do this, but there are some issues that I'm not clear about. I'd rather think about them earlier than later.

I checked in the beginning of this feature. You can now add to and delete from threads which should make this almost useable. I also made it so that folders remember if they are in the thread view. however, there is no navigation in threads right now (i.e. you can't do Next Message in threaded mode). that is coming next. Threading news folders don't work either which I've been told is because the backend for news needs to be worked on still. Feel free to file other thread bugs because I think this bug is too general to handle all of ones that I'm sure exist.

We decided to mark this fixed since threading, and adding and deleting in threads works. I will open up other bugs on news threading not working since I don't think that is part of this bug and on navigating through threads not working.

Ignore where I said news threading doesn't work. I thought it wasn't working before, but it seems to be working fine now.

Win_Nt 4.0 (1999-11-19-09 M12) Thread view works on Win_nt 4.0. Unable to re-test Mac and Linux. Wait for Monday's build

Linux Redhat 6.0 (1999-11-22-08 M12) Mac (1999-11-22-08 M12) Thread by subject works fine on all three systems.