Not looking for a solution -- just offering feedback before this moves to testing or stable.
I run deepin-unstable in VirtualBox.
The latest update I ran a couple days ago resulted in a system that boots to the login screen, then acts like it will continue booting, but returns to the login screen.
I reverted to a previous snapshot, changed to testing branch, and then updated: everything works fine.
Switched from testing to unstable and repeated update: resulted again in an endless loop at login.
By the way, I also run xfce-unstable in a VB, and it works fine. So the problem is definitely in recent updates to deepin.