I think drag and drop being not available is a big problem. Anyone has contact with inverse? Maybe drag and drop options will be implemented later?
/edit
I just doublechecked and in SOGo 2.x drag and drop just works. I wonder why it is not implemented in v3…
/edit2
According to SOGo bugtracker, this should be fixed with SOGo 3.0.1: http://sogo.nu/bugs/view.php?id=3497
I have sogo-3.0.1-1.centos6.x86_64 and can confirm that drag - drop does not work.
Then it does need to be reported as a bug…
/edit
I sent a message to the SOGo users mailinglist. Lets see what they come up with.
//edit:
Got a first reply: Hi, they added a menu entry for it, not “drag and drop”.
We should start a crowdfunding campaign and collect enough money for
them to start working on it.
A menu entry… seriously? … 
Its been like a year since this thread was active, but is still relevant at the moment.
I have NS 7.3RC and SOGo 3.2.4. But with this NS SOGo version its not yet possible to move drag and drop messages. SOGo claims to have fixed this issue in v3.1.5.
In their demo site the drag and drop is working. It has v3.2.5
This feature would be especially for marking/unmarking messages as spam, etc
Is it possible that it is the NS SOGo version that doesnt have this feature ?
Ver 3.2.5 Demo site here: http://demo.sogo.nu/SOGo/ (user: sogo1, password: sogo1).
You’re right, we should update our SOGo version to 3.2.5 a build the new rpms
3.2.6a is buildt
It works with the version I have, but if you want to drag and drop a message, firstly you must select it with the left button of your mouse, then move it.
workable here with 3.2.6a and Firefox 50.1
Stephdl
Is 3.2.6a in NS repos (if yes, which one) ?
soon in nethforge-testing
I’m really curious to know how you did it.
Did you built the rpms on your machine or using copr?
http://wiki.nethserver.org/doku.php?id=build_sogo_rpm&s[]=sogo
I did some doc, easy on NS7, but I miserably fail on el6 
Wonderful!!
With el6 I have a conflict
Transaction check error:
file /usr/bin from install of gnustep-make-2.6.1-1.x86_64 conflicts with file from package filesystem-2.4.30-3.el6.x86_64
filesystem comes from [base]
gnustep-make comes from [sogo-nightly]
If I use gnustep-make from epel (major version) the compilation fails :’(
You need to use all GNUstep dependencies from SOGo: it’s a nightmare.
Don’t waste your time on it 
Thanks for sharing your work, I hope it helps future contributors 